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2026 · test · Mathematics · Grade 12

Grade 12 Mathematics — class test (45 min)

Notes

Class test. Answer all four questions. Show a formula, substitution and answer with units.

60 min · 115 Marks · 30 questions

Learn the paper in the app: notes, a marks breakdown, the formula you need, and the board working. You do not need to download it.

Question breakdown

  1. 1 · 10 Marks

    ddx (x⁵)=

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: ddx (x⁵) =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: ddx (x⁵) =. Circle that word — that is the missing variable.

    Find

    We are required to find: ddx (x⁵) =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: Power rule: n x^{n−1} = 5x⁴. Then substitute the given, one line at a time, to get ddx (x⁵) =.

    In other words — as if you have never seen this before

    If you have never seen this before: Power rule: n x^{n−1} = 5x⁴. We will name a method in words, write the formula with no numbers, then substitute one line at a time.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    Power rule: n xⁿ⁻¹=5x⁴.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: ddx (x⁵) =. Circle that word — that is the missing variable. Find: We are required to find: ddx (x⁵) =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: Power rule: n x^{n−1} = 5x⁴. Then substitute the given, one line at a time, to get ddx (x⁵) =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      Power rule: n xⁿ⁻¹=5x⁴.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      Power rule: n xⁿ⁻¹=5x⁴.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      5x⁴

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    5x⁴

    Copy onto your answer sheet — in this order

    Answer: 5x⁴

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  2. 2 · 10 Marks

    S_∞ of 16 + 8 + 4 + … =

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: S_∞ of 16 + 8 + 4 + … =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 16 · 8 · 4. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: S_∞ of 16 + 8 + 4 + … =. Circle that word — that is the missing variable.

    Find

    We are required to find: S_∞ of 16 + 8 + 4 + … =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: a = 16, r = 12. Then substitute the given, one line at a time, to get S_∞ of 16 + 8 + 4 + … =.

    In other words — as if you have never seen this before

    If you have never seen this before: a = 16, r = 12. S = 16(1−0.5)=32. We will name a method in words, write the formula with no numbers, then substitute one line at a time.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 16 · 8 · 4. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    a=16, r=12. S=16(1−0.5)=32.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 16 · 8 · 4. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: S_∞ of 16 + 8 + 4 + … =. Circle that word — that is the missing variable. Find: We are required to find: S_∞ of 16 + 8 + 4 + … =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: a = 16, r = 12. Then substitute the given, one line at a time, to get S_∞ of 16 + 8 + 4 + … =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 16 · 8 · 4. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      a=16, r=12. S=16(1−0.5)=32.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      a=16, r=12. S=16(1−0.5)=32.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      32

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    32

    Copy onto your answer sheet — in this order

    Answer: 32

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  3. 3 · 10 Marks

    log₂ 16=

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: log₂ 16 =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 16. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: log₂ 16 =. Circle that word — that is the missing variable.

    Find

    We are required to find: log₂ 16 =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: 2⁴ = 16. Then substitute the given, one line at a time, to get log₂ 16 =.

    In other words — as if you have never seen this before

    If you have never seen this before: 2⁴ = 16. We will name a method in words, write the formula with no numbers, then substitute one line at a time.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 16. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    2⁴=16.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 16. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: log₂ 16 =. Circle that word — that is the missing variable. Find: We are required to find: log₂ 16 =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: 2⁴ = 16. Then substitute the given, one line at a time, to get log₂ 16 =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 16. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      2⁴=16.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      2⁴=16.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      4

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    4

    Copy onto your answer sheet — in this order

    Answer: 4

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  4. 4 · 10 Marks

    Stationary points of f(x) = x³ − 12x + 1 at x =

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Stationary points of f(x) = x³ − 12x + 1 at x =

    In other words — as if you have never seen this before

    If you have never seen this before: f' = 3x² − 12 = 0 → x² = 4 → x = ±2. We will name a method in words, write the formula with no numbers, then substitute one line at a time.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 12x · 1 at. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    f'=3x²−12=0→x²=4→x=±2.

    4. Step-by-step working

    1. 01 / 07

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 07

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 12x · 1 at. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    3. 03 / 07

      Step C — Name the method in words

      f'=3x²−12=0→x²=4→x=±2.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    4. 04 / 07

      Working

      f'=3x²−12=0→x²=4→x=±2.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    5. 05 / 07

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    6. 06 / 07

      Step F — Box the answer with its unit

      ±2

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    7. 07 / 07

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    ±2

    Copy onto your answer sheet — in this order

    Answer: ±2

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  5. 5 · 2 Marks

    loga a=

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: log_a a =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: log_a a =. Circle that word — that is the missing variable.

    Find

    We are required to find: log_a a =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: a¹ = a. Then substitute the given, one line at a time, to get log_a a =.

    In other words — as if you have never seen this before

    a¹=a.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    a¹=a.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: log_a a =. Circle that word — that is the missing variable. Find: We are required to find: log_a a =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: a¹ = a. Then substitute the given, one line at a time, to get log_a a =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      a¹=a.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      a¹=a.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      1

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    1

    Copy onto your answer sheet — in this order

    Answer: 1

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  6. 6 · 2 Marks

    Present value of an annuity is used for

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Present value of an annuity is used for

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Present value of an annuity is used for. Circle that word — that is the missing variable.

    Find

    We are required to find: Present value of an annuity is used for. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: P formula discounts future payments. Then substitute the given, one line at a time, to get Present value of an annuity is used for.

    In other words — as if you have never seen this before

    P formula discounts future payments.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    P formula discounts future payments.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Present value of an annuity is used for. Circle that word — that is the missing variable. Find: We are required to find: Present value of an annuity is used for. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: P formula discounts future payments. Then substitute the given, one line at a time, to get Present value of an annuity is used for.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      P formula discounts future payments.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      P formula discounts future payments.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      loanshow much you still owe

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    loanshow much you still owe

    Copy onto your answer sheet — in this order

    Answer: loanshow much you still owe

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  7. 7 · 3 Marks

    S_∞ of 2 + 4 + 8 + 16 + … is

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: S_∞ of 2 + 4 + 8 + 16 + … is

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 2 · 4 · 8 · 16. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: S_∞ of 2 + 4 + 8 + 16 + … is. Circle that word — that is the missing variable.

    Find

    We are required to find: S_∞ of 2 + 4 + 8 + 16 + … is. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: r = 2, |r| ≥ 1. Then substitute the given, one line at a time, to get S_∞ of 2 + 4 + 8 + 16 + … is.

    In other words — as if you have never seen this before

    r=2, |r| ≥ 1. Do not write 2(1−2)=−2.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 2 · 4 · 8 · 16. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    r=2, |r| ≥ 1. Do not write 2(1−2)=−2.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 2 · 4 · 8 · 16. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: S_∞ of 2 + 4 + 8 + 16 + … is. Circle that word — that is the missing variable. Find: We are required to find: S_∞ of 2 + 4 + 8 + 16 + … is. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: r = 2, |r| ≥ 1. Then substitute the given, one line at a time, to get S_∞ of 2 + 4 + 8 + 16 + … is.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 2 · 4 · 8 · 16. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      r=2, |r| ≥ 1. Do not write 2(1−2)=−2.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      r=2, |r| ≥ 1. Do not write 2(1−2)=−2.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      does not exist (diverges)

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    does not exist (diverges)

    Copy onto your answer sheet — in this order

    Answer: does not exist (diverges)

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  8. 8 · 2 Marks · Area, sine and cosine rules

    ddx (4x³)=

    Formulas

    Area=½ ab sin C

    Area rule

    c²=a²+b²−2ab cos C

    Cosine rule

    Notes: f(x)=4x³. Unknown: f'(x).

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: ddx (4x³) =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 4x³. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: ddx (4x³) =. Circle that word — that is the missing variable.

    Find

    We are required to find: ddx (4x³) =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    Write ddx (axⁿ)=an xⁿ⁻¹ with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives ddx (4x³) =.

    In other words — as if you have never seen this before

    Power rule: ddx (axⁿ)=a n xⁿ⁻¹.

    2. What do we already know?

    f(x)=4x³. Unknown: f'(x).

    3. Which method — and why this one?

    Power rule: ddx (axⁿ)=a n xⁿ⁻¹.

    4. Step-by-step working

    1. 01 / 05

      Write the power rule

      Bring the 3 down, multiply by 4, drop the power by 1.

      ddx (axⁿ)=an xⁿ⁻¹

      Why this step: Write the formula before numbers. The memo awards a method mark for the law even if a digit slips later.

    2. 02 / 05

      Calculate

      4×3 x²=12x².

      12x²

      Why this step: One job per line so you can find a slip, and so a marker can follow the marks.

    3. 03 / 05

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    4. 04 / 05

      Step F — Box the answer with its unit

      12x²

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    5. 05 / 05

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    12x²

    Copy onto your answer sheet — in this order

    Formula: ddx (axⁿ)=an xⁿ⁻¹

    Answer: 12x²

    6. Check it like a marker

    Degree drops by 1: cubic → quadratic. Coefficient 12 is 4×3.

    7. A trap first-timers fall into

    Do not write 4x² (forgot to multiply by 3) or 12x³ (forgot to drop the power).

  9. 9 · 4 Marks · First principles of differentiation

    From first principles, derivative of f(x)=x² at x=3 is

    Formulas

    f'(x)=limh→0[f(x+h) − f(x)]h

    Definition of the derivative

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: From first principles, derivative of f(x)=x² at x=3 is

    In other words — as if you have never seen this before

    f'=2x so at 3 is 6. Or lim [ (3+h)²−9]h=6.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 3 is. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    f'=2x so at 3 is 6. Or lim [ (3+h)²−9]h=6.

    4. Step-by-step working

    1. 01 / 07

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 07

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 3 is. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    3. 03 / 07

      Step C — Name the method in words

      f'=2x so at 3 is 6. Or lim [ (3+h)²−9]h=6.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    4. 04 / 07

      Working

      f'=2x so at 3 is 6. Or lim [ (3+h)²−9]h=6.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    5. 05 / 07

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    6. 06 / 07

      Step F — Box the answer with its unit

      6

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    7. 07 / 07

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    6

    Copy onto your answer sheet — in this order

    Answer: 6

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  10. 10 · 3 Marks · Arithmetic & geometric series

    Geometric a=5, r=2. T₄=

    Formulas

    Tₙ=a rⁿ⁻¹

    Geometric nth term — exponent is n minus 1

    Sₙ=n2 [2a + (n−1)d]

    Arithmetic sum

    Sₙ=a(rⁿ − 1)(r − 1), r ≠ 1

    Geometric sum

    Notes: First term 5, common ratio 2. Fourth term.

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Geometric a=5, r=2. T₄ =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 5 · 2. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: T₄ =. Circle that word — that is the missing variable.

    Find

    We are required to find: T₄ =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    Write Tₙ = a rⁿ⁻¹ with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives T₄ =.

    In other words — as if you have never seen this before

    Tₙ=a rⁿ⁻¹. T₄=5×2³=5×8=40.

    2. What do we already know?

    First term 5, common ratio 2. Fourth term.

    3. Which method — and why this one?

    Tₙ=a rⁿ⁻¹. T₄=5×2³=5×8=40.

    4. Step-by-step working

    1. 01 / 05

      Write Tₙ = arⁿ⁻¹

      The exponent is n minus 1, not n.

      Tₙ=a rⁿ⁻¹

      Why this step: Write the formula before numbers. The memo awards a method mark for the law even if a digit slips later.

    2. 02 / 05

      Substitute

      T₄=5×2³=40.

      T₄=40

      Why this step: One job per line so you can find a slip, and so a marker can follow the marks.

    3. 03 / 05

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    4. 04 / 05

      Step F — Box the answer with its unit

      40

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    5. 05 / 05

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    40

    Copy onto your answer sheet — in this order

    Formula: Tₙ=a rⁿ⁻¹

    Answer: 40

    6. Check it like a marker

    Sequence: 5, 10, 20, 40. Fourth term 40.

    7. A trap first-timers fall into

    2⁴ = 16 would give T₅ if you use rⁿ instead of rⁿ⁻¹.

  11. 11 · 4 Marks

    Which formula is future value of an ordinary annuity?

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Which formula is future value of an ordinary annuity?

    In other words — as if you have never seen this before

    Money going in grows to F. Loans use P.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    Money going in grows to F. Loans use P.

    4. Step-by-step working

    1. 01 / 07

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 07

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    3. 03 / 07

      Step C — Name the method in words

      Money going in grows to F. Loans use P.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    4. 04 / 07

      Working

      Money going in grows to F. Loans use P.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    5. 05 / 07

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    6. 06 / 07

      Step F — Box the answer with its unit

      F=x[((1+i)ⁿ−1)/i]

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    7. 07 / 07

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    F=x[((1+i)ⁿ−1)/i]

    Copy onto your answer sheet — in this order

    Answer: F=x[((1+i)ⁿ−1)/i]

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  12. 12 · 4 Marks

    Stationary points of f(x)=x² − 4x: f'(x)=0 at

    Notes: f(x)=x² − 4x. Stationary means the derivative is zero.

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Stationary points of f(x)=x² − 4x: f'(x)=0 at

    In other words — as if you have never seen this before

    Differentiate, set equal to zero, solve for x.

    2. What do we already know?

    f(x)=x² − 4x. Stationary means the derivative is zero.

    3. Which method — and why this one?

    Differentiate, set equal to zero, solve for x.

    4. Step-by-step working

    1. 01 / 05

      Differentiate

      f'(x)=2x−4.

      f'=2x−4

      Why this step: Write the formula before numbers. The memo awards a method mark for the law even if a digit slips later.

    2. 02 / 05

      Set to zero

      2x−4=0→2x=4→x=2.

      x=2

      Why this step: One job per line so you can find a slip, and so a marker can follow the marks.

    3. 03 / 05

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    4. 04 / 05

      Step F — Box the answer with its unit

      x=2

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    5. 05 / 05

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    x=2

    Copy onto your answer sheet — in this order

    Formula: f'=2x−4

    Answer: x=2

    6. Check it like a marker

    Second derivative f''=2>0 so it is a minimum at x=2. f(2)=4−8=−4.

    7. A trap first-timers fall into

    Do not solve f(x)=0 — those are x-intercepts (0 and 4), not stationary points.

  13. 13 · 2 Marks · Area, sine and cosine rules

    ddx (x³)=

    Formulas

    Area=½ ab sin C

    Area rule

    c²=a²+b²−2ab cos C

    Cosine rule

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: ddx (x³) =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: ddx (x³) =. Circle that word — that is the missing variable.

    Find

    We are required to find: ddx (x³) =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: Power rule: n x^{n−1}. Then substitute the given, one line at a time, to get ddx (x³) =.

    In other words — as if you have never seen this before

    Power rule: n xⁿ⁻¹.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    Power rule: n xⁿ⁻¹.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: ddx (x³) =. Circle that word — that is the missing variable. Find: We are required to find: ddx (x³) =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: Power rule: n x^{n−1}. Then substitute the given, one line at a time, to get ddx (x³) =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      Power rule: n xⁿ⁻¹.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      Power rule: n xⁿ⁻¹.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      3x²

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    3x²

    Copy onto your answer sheet — in this order

    Answer: 3x²

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  14. 14 · 2 Marks · Arithmetic & geometric series

    Arithmetic: a=5, d=3. T₈=

    Formulas

    Tₙ=a rⁿ⁻¹

    Geometric nth term — exponent is n minus 1

    Sₙ=n2 [2a + (n−1)d]

    Arithmetic sum

    Sₙ=a(rⁿ − 1)(r − 1), r ≠ 1

    Geometric sum

    Notes: a=5. d=3. n=8. Unknown: Tn.

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Arithmetic: a=5, d=3. T₈ =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 5 · 3. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: T₈ =. Circle that word — that is the missing variable.

    Find

    We are required to find: T₈ =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    Write T₈ = 26 with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives T₈ =.

    In other words — as if you have never seen this before

    T_n = a + (n − 1)d. Eight terms means 7 steps of d, not 8.

    2. What do we already know?

    a=5. d=3. n=8. Unknown: Tn.

    3. Which method — and why this one?

    T_n = a + (n − 1)d. Eight terms means 7 steps of d, not 8.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 5 · 3. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: T₈ =. Circle that word — that is the missing variable. Find: We are required to find: T₈ =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: Write T₈ = 26 with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives T₈ =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      a=5. d=3. n=8. Unknown: Tn.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      T_n = a + (n − 1)d. Eight terms means 7 steps of d, not 8.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Formula

      T₈=5+7×3=5+21=26.

      T₈=26

      Why this step: Write the formula before numbers. The memo awards a method mark even if a digit slips later.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      26

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    26

    Copy onto your answer sheet — in this order

    Formula: T₈=26

    Answer: 26

    6. Check it like a marker

    5,8,11,14,17,20,23,26. The eighth is 26.

    7. A trap first-timers fall into

    5 + 8×3 = 29 uses n instead of n−1.

  15. 15 · 3 Marks · Compound angles

    ddx not on Paper 2. Which topic is Paper 2?

    hbθ

    Formulas

    sin(A + B)=sin A cos B+cos A sin B

    Sine compound

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: ddx not on Paper 2. Which topic is Paper 2?

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 2 · 2. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Which topic is Paper 2. Circle that word — that is the missing variable.

    Find

    We are required to find: Which topic is Paper 2. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: Trigonometry. Then substitute the given, one line at a time, to get Which topic is Paper 2.

    In other words — as if you have never seen this before

    Trigonometry

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 2 · 2. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    Trigonometry

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 2 · 2. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Which topic is Paper 2. Circle that word — that is the missing variable. Find: We are required to find: Which topic is Paper 2. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: Trigonometry. Then substitute the given, one line at a time, to get Which topic is Paper 2.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 2 · 2. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      Trigonometry

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Reason

      Calculus and finance sit on Paper 1.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      Trigonometry

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    Trigonometry

    Copy onto your answer sheet — in this order

    Answer: Trigonometry

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  16. 16 · 4 Marks · Compound angles

    A vertical pole 8 m, observer 15 m away. Angle of elevation tan⁻¹(8/15) ≈

    hbθ

    Formulas

    sin(A + B)=sin A cos B+cos A sin B

    Sine compound

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: A vertical pole 8 m, observer 15 m away. Angle of elevation tan⁻¹(8/15) ≈

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 8 m · 15 m · 8/ · 15. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Angle of elevation tan⁻¹(8/15) ≈. Circle that word — that is the missing variable.

    Find

    We are required to find: Angle of elevation tan⁻¹(8/15) ≈. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: tan θ = oppositeadjacent=815. Then substitute the given, one line at a time, to get Angle of elevation tan⁻¹(8/15) ≈.

    In other words — as if you have never seen this before

    tan θ = oppositeadjacent=815.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 8 m · 15 m · 8/ · 15. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    tan θ = oppositeadjacent=815.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 8 m · 15 m · 8/ · 15. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Angle of elevation tan⁻¹(8/15) ≈. Circle that word — that is the missing variable. Find: We are required to find: Angle of elevation tan⁻¹(8/15) ≈. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: tan θ = oppositeadjacent=815. Then substitute the given, one line at a time, to get Angle of elevation tan⁻¹(8/15) ≈.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 8 m · 15 m · 8/ · 15. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      tan θ = oppositeadjacent=815.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      tan θ = oppositeadjacent=815.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      28.1°

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    28.1°

    Copy onto your answer sheet — in this order

    Answer: 28.1°

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  17. 17 · 2 Marks · Arithmetic & geometric series

    S_∞ of a geometric series exists only when

    Formulas

    Tₙ=a rⁿ⁻¹

    Geometric nth term — exponent is n minus 1

    Sₙ=n2 [2a + (n−1)d]

    Arithmetic sum

    Sₙ=a(rⁿ − 1)(r − 1), r ≠ 1

    Geometric sum

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: S_∞ of a geometric series exists only when

    In other words — as if you have never seen this before

    Terms must shrink. |r| ≥ 1 ⇒ the series diverges.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    Terms must shrink. |r| ≥ 1 ⇒ the series diverges.

    4. Step-by-step working

    1. 01 / 07

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 07

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    3. 03 / 07

      Step C — Name the method in words

      Terms must shrink. |r| ≥ 1 ⇒ the series diverges.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    4. 04 / 07

      Working

      Terms must shrink. |r| ≥ 1 ⇒ the series diverges.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    5. 05 / 07

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    6. 06 / 07

      Step F — Box the answer with its unit

      |r| < 1

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    7. 07 / 07

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    |r| < 1

    Copy onto your answer sheet — in this order

    Answer: |r| < 1

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  18. 18 · 3 Marks

    f'(x) = 0 for f(x) = x² − 8x + 3 at

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: f'(x) = 0 for f(x) = x² − 8x + 3 at

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 0 for · 8x · 3 at. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: f'(x) = 0 for f(x) = x² − 8x + 3 at. Circle that word — that is the missing variable.

    Find

    We are required to find: f'(x) = 0 for f(x) = x² − 8x + 3 at. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: x = 4. Then substitute the given, one line at a time, to get f'(x) = 0 for f(x) = x² − 8x + 3 at.

    In other words — as if you have never seen this before

    x=4

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 0 for · 8x · 3 at. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    x=4

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 0 for · 8x · 3 at. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: f'(x) = 0 for f(x) = x² − 8x + 3 at. Circle that word — that is the missing variable. Find: We are required to find: f'(x) = 0 for f(x) = x² − 8x + 3 at. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: x = 4. Then substitute the given, one line at a time, to get f'(x) = 0 for f(x) = x² − 8x + 3 at.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 0 for · 8x · 3 at. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      x=4

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      f' = 2x − 8 = 0 → x = 4. Stationary point sits where the gradient is zero.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      x=4

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    x=4

    Copy onto your answer sheet — in this order

    Answer: x=4

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  19. 19 · 4 Marks

    log₅ 125=

    Notes: log₅ 125. In words: “5 to the what equals 125?”

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: log₅ 125 =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 125. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: log₅ 125 =. Circle that word — that is the missing variable.

    Find

    We are required to find: log₅ 125 =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    Write 5ˣ = 125 with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives log₅ 125 =.

    In other words — as if you have never seen this before

    A logarithm is an index. Convert to 5ˣ = 125, then notice 5³ = 125.

    2. What do we already know?

    log₅ 125. In words: “5 to the what equals 125?”

    3. Which method — and why this one?

    A logarithm is an index. Convert to 5ˣ = 125, then notice 5³ = 125.

    4. Step-by-step working

    1. 01 / 05

      Rewrite as an exponential

      log₅ 125=x⇔5ˣ=125.

      5ˣ=125

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    2. 02 / 05

      Recognise the power

      5¹=5, 5²=25, 5³=125. So x=3.

      x=3

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    3. 03 / 05

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    4. 04 / 05

      Step F — Box the answer with its unit

      3

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    5. 05 / 05

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    3

    Copy onto your answer sheet — in this order

    Formula: 5ˣ=125

    Answer: 3

    6. Check it like a marker

    5³=5×5×5=125. Yes.

    7. A trap first-timers fall into

    Writing 25 (that is 1255) or 5 (the base). A log is not a divide.

  20. 20 · 4 Marks

    Solve 2ˣ=8

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Solve 2ˣ = 8

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 2 · 8. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Solve 2ˣ = 8. Circle that word — that is the missing variable.

    Find

    We are required to find: Solve 2ˣ = 8. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: 8=2³. Then substitute the given, one line at a time, to get Solve 2ˣ = 8.

    In other words — as if you have never seen this before

    8=2³.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 2 · 8. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    8=2³.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 2 · 8. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Solve 2ˣ = 8. Circle that word — that is the missing variable. Find: We are required to find: Solve 2ˣ = 8. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: 8=2³. Then substitute the given, one line at a time, to get Solve 2ˣ = 8.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 2 · 8. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      8=2³.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      8=2³.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      x=3

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    x=3

    Copy onto your answer sheet — in this order

    Answer: x=3

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  21. 21 · 3 Marks

    6C2=

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: 6C2 =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 6C · 2. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: 6C2 =. Circle that word — that is the missing variable.

    Find

    We are required to find: 6C2 =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: 15. Then substitute the given, one line at a time, to get 6C2 =.

    In other words — as if you have never seen this before

    15

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 6C · 2. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    15

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 6C · 2. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: 6C2 =. Circle that word — that is the missing variable. Find: We are required to find: 6C2 =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: 15. Then substitute the given, one line at a time, to get 6C2 =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 6C · 2. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      15

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      6! / (2! 4!) = (6 × 5) / 2 = 15. Combinations do not care about order — that is why we divide by 2!.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      15

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    15

    Copy onto your answer sheet — in this order

    Answer: 15

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  22. 22 · 3 Marks · Similarity & proportion

    AA similarity requires

    hbθ

    Formulas

    AA similarity ⇒ corresponding sides proportional

    AA similarity

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: AA similarity requires

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: AA similarity requires. Circle that word — that is the missing variable.

    Find

    We are required to find: AA similarity requires. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: two equal corresponding angles. Then substitute the given, one line at a time, to get AA similarity requires.

    In other words — as if you have never seen this before

    two equal corresponding angles

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    two equal corresponding angles

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: AA similarity requires. Circle that word — that is the missing variable. Find: We are required to find: AA similarity requires. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: two equal corresponding angles. Then substitute the given, one line at a time, to get AA similarity requires.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      two equal corresponding angles

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Reason

      AA is sufficient.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      two equal corresponding angles

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    two equal corresponding angles

    Copy onto your answer sheet — in this order

    Answer: two equal corresponding angles

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  23. 23 · 4 Marks

    Predicting y outside the given x-range is

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Predicting y outside the given x-range is

    In other words — as if you have never seen this before

    Outside the data cloud.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    Outside the data cloud.

    4. Step-by-step working

    1. 01 / 07

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 07

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    3. 03 / 07

      Step C — Name the method in words

      Outside the data cloud.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    4. 04 / 07

      Working

      Outside the data cloud.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    5. 05 / 07

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    6. 06 / 07

      Step F — Box the answer with its unit

      extrapolation

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    7. 07 / 07

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    extrapolation

    Copy onto your answer sheet — in this order

    Answer: extrapolation

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  24. 24 · 3 Marks

    log₃ 81=

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: log₃ 81 =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 81. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: log₃ 81 =. Circle that word — that is the missing variable.

    Find

    We are required to find: log₃ 81 =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: 4. Then substitute the given, one line at a time, to get log₃ 81 =.

    In other words — as if you have never seen this before

    4

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 81. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    4

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 81. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: log₃ 81 =. Circle that word — that is the missing variable. Find: We are required to find: log₃ 81 =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: 4. Then substitute the given, one line at a time, to get log₃ 81 =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 81. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      4

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      3⁴ = 81, so the log is 4. Ask: “3 to the what equals 81?”

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      4

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    4

    Copy onto your answer sheet — in this order

    Answer: 4

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  25. 25 · 2 Marks

    5P2=

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: 5P2 =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 5P · 2. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: 5P2 =. Circle that word — that is the missing variable.

    Find

    We are required to find: 5P2 =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: 5×4 = 20. Then substitute the given, one line at a time, to get 5P2 =.

    In other words — as if you have never seen this before

    5×4=20.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 5P · 2. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    5×4=20.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 5P · 2. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: 5P2 =. Circle that word — that is the missing variable. Find: We are required to find: 5P2 =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: 5×4 = 20. Then substitute the given, one line at a time, to get 5P2 =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 5P · 2. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      5×4=20.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      5×4=20.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      20

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    20

    Copy onto your answer sheet — in this order

    Answer: 20

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  26. 26 · 2 Marks · First principles of differentiation

    f(x)=x². From first principles f'(x)=

    Formulas

    f'(x)=limh→0[f(x+h) − f(x)]h

    Definition of the derivative

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: f(x)=x². From first principles f'(x) =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: From first principles f'(x) =. Circle that word — that is the missing variable.

    Find

    We are required to find: From first principles f'(x) =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: [2xh + h²]h. Then substitute the given, one line at a time, to get From first principles f'(x) =.

    In other words — as if you have never seen this before

    [2xh + h²]h→2x as h→0.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    [2xh + h²]h→2x as h→0.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: From first principles f'(x) =. Circle that word — that is the missing variable. Find: We are required to find: From first principles f'(x) =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: [2xh + h²]h. Then substitute the given, one line at a time, to get From first principles f'(x) =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      [2xh + h²]h→2x as h→0.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      [2xh + h²]h→2x as h→0.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      2x

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    2x

    Copy onto your answer sheet — in this order

    Answer: 2x

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  27. 27 · 2 Marks · Compound angles

    sin 15° in surd form uses

    hbθ

    Formulas

    sin(A + B)=sin A cos B+cos A sin B

    Sine compound

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: sin 15° in surd form uses

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 15°. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: sin 15° in surd form uses. Circle that word — that is the missing variable.

    Find

    We are required to find: sin 15° in surd form uses. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: sin(45−30). Then substitute the given, one line at a time, to get sin 15° in surd form uses.

    In other words — as if you have never seen this before

    sin(45−30)

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 15°. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    sin(45−30)

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 15°. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: sin 15° in surd form uses. Circle that word — that is the missing variable. Find: We are required to find: sin 15° in surd form uses. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: sin(45−30). Then substitute the given, one line at a time, to get sin 15° in surd form uses.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 15°. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      sin(45−30)

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Reason

      Compound angle.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      sin(45−30)

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    sin(45−30)

    Copy onto your answer sheet — in this order

    Answer: sin(45−30)

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  28. 28 · 2 Marks

    ddx (x⁴)=

    Notes: f(x)=x⁴. Power rule.

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: ddx (x⁴) =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: ddx (x⁴) =. Circle that word — that is the missing variable.

    Find

    We are required to find: ddx (x⁴) =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    Write ddx xⁿ = n xⁿ⁻¹ with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives ddx (x⁴) =.

    In other words — as if you have never seen this before

    n xⁿ⁻¹. 4x³.

    2. What do we already know?

    f(x)=x⁴. Power rule.

    3. Which method — and why this one?

    n xⁿ⁻¹. 4x³.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: ddx (x⁴) =. Circle that word — that is the missing variable. Find: We are required to find: ddx (x⁴) =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: Write ddx xⁿ = n xⁿ⁻¹ with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives ddx (x⁴) =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      f(x)=x⁴. Power rule.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      n xⁿ⁻¹. 4x³.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Power rule

      Bring 4 down, drop the power to 3.

      ddx xⁿ=n xⁿ⁻¹

      Why this step: Write the formula before numbers. The memo awards a method mark for the law even if a digit slips later.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      4x³

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    4x³

    Copy onto your answer sheet — in this order

    Formula: ddx xⁿ=n xⁿ⁻¹

    Answer: 4x³

    6. Check it like a marker

    Integral of 4x³ is x⁴ + C, inverse check.

    7. A trap first-timers fall into

    x⁵5 is the integral, not the derivative.

  29. 29 · 3 Marks

    S_∞ of 8 + 4 + 2 + … =

    Notes: a = 8, next is 4, then 2. Geometric with r = 12.

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: S_∞ of 8 + 4 + 2 + … =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 8 · 4 · 2. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: S_∞ of 8 + 4 + 2 + … =. Circle that word — that is the missing variable.

    Find

    We are required to find: S_∞ of 8 + 4 + 2 + … =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    Write r = 12 with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives S_∞ of 8 + 4 + 2 + … =.

    In other words — as if you have never seen this before

    |r|<1 so S∞=a(1−r).

    2. What do we already know?

    a = 8, next is 4, then 2. Geometric with r = 12.

    3. Which method — and why this one?

    |r|<1 so S∞=a(1−r).

    4. Step-by-step working

    1. 01 / 05

      Find r

      r=48=1/2. |12|<1, converges.

      r=12

      Why this step: One job per line so you can find a slip, and so a marker can follow the marks.

    2. 02 / 05

      Substitute

      S∞=8(1−1/2)=8(1/2)=16.

      S∞=16

      Why this step: Write the formula before numbers. The memo awards a method mark for the law even if a digit slips later.

    3. 03 / 05

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    4. 04 / 05

      Step F — Box the answer with its unit

      16

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    5. 05 / 05

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    16

    Copy onto your answer sheet — in this order

    Formula: r=12

    Answer: 16

    6. Check it like a marker

    Partial sums 8, 12, 14, 15, 15.5… climbing to 16.

    7. A trap first-timers fall into

    Do not use the arithmetic sum formula. Do not write 8(1+1/2).

  30. 30 · 3 Marks · Compound angles

    sin(A − B) expands to

    hbθ

    Formulas

    sin(A + B)=sin A cos B+cos A sin B

    Sine compound

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: sin(A − B) expands to

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: sin(A − B) expands to. Circle that word — that is the missing variable.

    Find

    We are required to find: sin(A − B) expands to. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: sinA cosB − cosA sinB. Then substitute the given, one line at a time, to get sin(A − B) expands to.

    In other words — as if you have never seen this before

    sinA cosB − cosA sinB

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    sinA cosB − cosA sinB

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: sin(A − B) expands to. Circle that word — that is the missing variable. Find: We are required to find: sin(A − B) expands to. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: sinA cosB − cosA sinB. Then substitute the given, one line at a time, to get sin(A − B) expands to.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      sinA cosB − cosA sinB

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      Compound-angle sine with a minus: the minus stays in the middle. Plus would be sin(A+B).

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      sinA cosB − cosA sinB

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    sinA cosB − cosA sinB

    Copy onto your answer sheet — in this order

    Answer: sinA cosB − cosA sinB

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

Ntsako · fx-991ZA PLUS. Tap to calculate.