Standard difficulty · 20 questions · 40 marks
Show your working for Sections B and C. Answers are on the last page — try every question first!
Binomial Theorem · AW-11M-BIN-2026-V1 · For parents — fold back or tear off before handing the sheet to your child.
| Q | Answer | Working |
|---|---|---|
| 1 | (d) 6 | — |
| 2 | (c) 3,584 | term with x5: 8C3 × (4)3 |
| 3 | (d) 6 | term 3: 4C2 × (−1)2 |
| 4 | (b) 32 | put x = 1: (2)5 |
| 5 | (c) n + 1 | — |
| 6 | (d) −945x4 | Tᵣ+1 = ⁿCᵣ x7−ʳ aʳ with r = 3 |
| 7 | (c) 92,236,816 | (100 − 2)4 |
| 8 | (a) Both A and R are true, and R is the correct explanation of A. | A is true: 14C4 = 1,001; 14C10 = 1,001. R is true and explains A. |
| 9 | 81x4 + 216x3 + 216x2 + 96x + 16 | coefficients 4C0, 4C1, 4C2, 4C3, 4C4 |
| 10 | 12,288 | 6C5 × (2)1 × (4)5 |
| 11 | 1,092,727 | (100 + 3)3 = 3C0 × 1003 × (3)0 + 3C1 × 1002 × (3)1 + 3C2 × 1001 × (3)2 + … |
| 12 | 27 | x^(2(3 − r) − r) = x0 when r = 2 |
| 13 | 160x3 and −640x2 | n = 5 is odd: terms 3 and 4 |
| 14 | 12x5 + 40x3 + 12x | terms with even powers of the second term cancel |
| 15 | 405x | T5 = 5C4 x1 (−3)4 |
| 16 | 524,288; 262,144 | put x = 1 in (1 + x)19; odd and even terms split the total equally |
| 17 | 243x5 + 1215x4 + 2430x3 + 2430x2 + 1215x + 243; coefficient of x4: 1,215; sum 7,776 | Tᵣ+1 = ⁿCᵣ (px)ⁿ−ʳ qʳ |
| 18 | 674 | the odd terms cancel: 2(a4 + 6a2b2 + b4) with a2 = 6, b2 = 7 |
| 19 | 1 | 528 = (6 − 1)28: every term except the last has a factor 6; the last is (−1)28 = 1 |
| 20 | 1.0406 | (1 + 0.01)4 ≈ 1 + 4 × 0.01 + 6 × 0.0001 |