Year 11 Integration (Polynomials) Worksheet — Level 3 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 11 calculus worksheet.
Year 11 Integration (Polynomials) Worksheet — Level 3 — Practice Set 4 — Answers
Use the rule ∫ xⁿ dx = xⁿ⁺¹ / (n+1) + C.
1.Evaluate ∫ from 0 to 2 of (20x4 − 6x − 2) dx
Answer: 112
- ∫ 20x4 dx = 4x5
- ∫ −6x dx = −3x2
- ∫ −2 dx = −2x
- F(x) = 4x5 − 3x2 − 2x
- F(2) − F(0) = 112 − (0) = 112
2.Find ∫ (4x3 − 3x2 − 2) dx
Answer: x4 − x3 − 2x + C
- ∫ 4x3 dx = x4
- ∫ −3x2 dx = −x3
- ∫ −2 dx = −2x
- Don't forget the constant of integration, C
3.Find ∫ (10x4 + 4x3 + 4) dx
Answer: 2x5 + x4 + 4x + C
- ∫ 10x4 dx = 2x5
- ∫ 4x3 dx = x4
- ∫ 4 dx = 4x
- Don't forget the constant of integration, C
4.Evaluate ∫ from 0 to 2 of (−9x2 + 4x − 3) dx
Answer: −22
- ∫ −9x2 dx = −3x3
- ∫ 4x dx = 2x2
- ∫ −3 dx = −3x
- F(x) = −3x3 + 2x2 − 3x
- F(2) − F(0) = −22 − (0) = −22
5.Evaluate ∫ from 0 to 3 of (−3x2 − 4x + 4) dx
Answer: −33
- ∫ −3x2 dx = −x3
- ∫ −4x dx = −2x2
- ∫ 4 dx = 4x
- F(x) = −x3 − 2x2 + 4x
- F(3) − F(0) = −33 − (0) = −33
6.Find ∫ (20x4 − 3x2 − 4x) dx
Answer: 4x5 − x3 − 2x2 + C
- ∫ 20x4 dx = 4x5
- ∫ −3x2 dx = −x3
- ∫ −4x dx = −2x2
- Don't forget the constant of integration, C
7.Evaluate ∫ from 0 to 2 of (−15x4 − 12x3 − 4x) dx
Answer: −152
- ∫ −15x4 dx = −3x5
- ∫ −12x3 dx = −3x4
- ∫ −4x dx = −2x2
- F(x) = −3x5 − 3x4 − 2x2
- F(2) − F(0) = −152 − (0) = −152
8.Evaluate ∫ from 2 to 5 of (12x3 + 12x2 + 4x) dx
Answer: 2337
- ∫ 12x3 dx = 3x4
- ∫ 12x2 dx = 4x3
- ∫ 4x dx = 2x2
- F(x) = 3x4 + 4x3 + 2x2
- F(5) − F(2) = 2425 − (88) = 2337
9.Evaluate ∫ from 0 to 3 of (−8x3 + 6x2 − 4x) dx
Answer: −126
- ∫ −8x3 dx = −2x4
- ∫ 6x2 dx = 2x3
- ∫ −4x dx = −2x2
- F(x) = −2x4 + 2x3 − 2x2
- F(3) − F(0) = −126 − (0) = −126
10.Find ∫ (3x2 − 6x + 3) dx
Answer: x3 − 3x2 + 3x + C
- ∫ 3x2 dx = x3
- ∫ −6x dx = −3x2
- ∫ 3 dx = 3x
- Don't forget the constant of integration, C
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
- For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
- Celebrate what went well first, then pick one thing to work on next.
Great work. Here's what to try next: