Standard difficulty · 20 questions · 40 marks
Show your working for Sections B and C. Answers are on the last page — try every question first!
Limits and Derivatives · AW-11M-LMD-2026-V1 · For parents — fold back or tear off before handing the sheet to your child.
| Q | Answer | Working |
|---|---|---|
| 1 | (d) 33 | substitute directly |
| 2 | (c) 6,144 | naⁿ−1 = 6 × 45 |
| 3 | (d) 1 | use lim (sin θ)/θ = 1 |
| 4 | (b) 16x3 − 12x2 − 2x − 3 | d/dx xⁿ = nxⁿ−1 |
| 5 | (c) 1 | x in radians |
| 6 | (c) −2 | f′(x) = −12x2 + 6x + 4 |
| 7 | (a) −3 cos x + sin x − 5x4 | (sin x)′ = cos x, (cos x)′ = −sin x |
| 8 | (d) A is false, but R is true. | A is false: d/dx xⁿ = nxⁿ−1 with n = 8. R is true. |
| 9 | 1 | factorise: (x − 3)(x − 2); cancel and put x = 3 |
| 10 | 27 | lim (xⁿ − aⁿ)/(x − a) = naⁿ−1 = 3 × 32 |
| 11 | 7 | sin 4x ÷ x → 4; 3x ÷ x = 3 |
| 12 | 25x4 − 24x3 + 12x2 + 4x − 1 | differentiate term by term |
| 13 | −6x2 − 6x − 2 | u′v + uv′ = −2(x2 + 1) + (−2x − 3)(2x) |
| 14 | −18 ÷ (3x + 2)2 | (u′v − uv′)/v2 = [−6(3x + 2) − 3(−6x + 2)] ÷ (3x + 2)2 |
| 15 | f′(x) = 8x + 1; f′(3) = 25 | [f(x + h) − f(x)] ÷ h = 8x + 1 + 4h → 8x + 1 as h → 0 |
| 16 | 6x5 cos x − x6 sin x | product rule |
| 17 | (a) 6,144; (b) 3/4; (c) −2 | (c): x2 − r2 = (x − r)(x + r) |
| 18 | LHL = 4, RHL = 4; yes, the limit is 4 | put x = −3 in each expression |
| 19 | f′(x) = −6x2; f′(3) = −54; f′(0) = 0; the slope is −54 | — |
| 20 | f′(x) = −1 ÷ (x + 1)2 | [1/(x + h + 1) − 1/(x + 1)] ÷ h = −1 ÷ [(x + h + 1)(x + 1)] → −1/(x + 1)2 |