12th Grade Integration (Polynomials) Worksheet — Level 3 — Practice Set 4 — Answers
Answer sheet with worked solutions for the 12th Grade calculus worksheet.
12th Grade Integration (Polynomials) Worksheet — Level 3 — Practice Set 4 — Answers
Use the rule ∫ xⁿ dx = xⁿ⁺¹ / (n+1) + C.
1.Evaluate ∫ from 1 to 2 of (15x4 + 3x2 − 6x) dx
Answer: 91
- ∫ 15x4 dx = 3x5
- ∫ 3x2 dx = x3
- ∫ −6x dx = −3x2
- F(x) = 3x5 + x3 − 3x2
- F(2) − F(1) = 92 − (1) = 91
2.Evaluate ∫ from 0 to 3 of (15x4 − 3x2 − 1) dx
Answer: 699
- ∫ 15x4 dx = 3x5
- ∫ −3x2 dx = −x3
- ∫ −1 dx = −x
- F(x) = 3x5 − x3 − x
- F(3) − F(0) = 699 − (0) = 699
3.Evaluate ∫ from 2 to 5 of (20x4 + 4x3 + 8x) dx
Answer: 13065
- ∫ 20x4 dx = 4x5
- ∫ 4x3 dx = x4
- ∫ 8x dx = 4x2
- F(x) = 4x5 + x4 + 4x2
- F(5) − F(2) = 13225 − (160) = 13065
4.Evaluate ∫ from 2 to 3 of (10x4 − 12x3 − 6x2) dx
Answer: 189
- ∫ 10x4 dx = 2x5
- ∫ −12x3 dx = −3x4
- ∫ −6x2 dx = −2x3
- F(x) = 2x5 − 3x4 − 2x3
- F(3) − F(2) = 189 − (0) = 189
5.Find ∫ (−10x4 − 3x2 − 4x) dx
Answer: −2x5 − x3 − 2x2 + C
- ∫ −10x4 dx = −2x5
- ∫ −3x2 dx = −x3
- ∫ −4x dx = −2x2
- Don't forget the constant of integration, C
6.Find ∫ (−5x4 + 4x3 − 9x2) dx
Answer: −x5 + x4 − 3x3 + C
- ∫ −5x4 dx = −x5
- ∫ 4x3 dx = x4
- ∫ −9x2 dx = −3x3
- Don't forget the constant of integration, C
7.Find ∫ (−15x4 + 12x3 + 1) dx
Answer: −3x5 + 3x4 + x + C
- ∫ −15x4 dx = −3x5
- ∫ 12x3 dx = 3x4
- ∫ 1 dx = x
- Don't forget the constant of integration, C
8.Evaluate ∫ from 0 to 1 of (−15x4 − 4x3 − 6x2) dx
Answer: −6
- ∫ −15x4 dx = −3x5
- ∫ −4x3 dx = −x4
- ∫ −6x2 dx = −2x3
- F(x) = −3x5 − x4 − 2x3
- F(1) − F(0) = −6 − (0) = −6
9.Evaluate ∫ from 1 to 3 of (−5x4 − 4x3 + 9x2) dx
Answer: −244
- ∫ −5x4 dx = −x5
- ∫ −4x3 dx = −x4
- ∫ 9x2 dx = 3x3
- F(x) = −x5 − x4 + 3x3
- F(3) − F(1) = −243 − (1) = −244
10.Find ∫ (−5x4 − 12x3 − 4x) dx
Answer: −x5 − 3x4 − 2x2 + C
- ∫ −5x4 dx = −x5
- ∫ −12x3 dx = −3x4
- ∫ −4x dx = −2x2
- Don't forget the constant of integration, C
Marking tips
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