Answer: -cos x + C.
- A cos x + C
- B -cos x + C
- C sin x + C
- D -sin x + C
Correct answer: B. -cos x + C
Explanation: Integral of sin x = -cos x + C (since d/dx(-cos x) = sin x).
The exact area under the curve from a to b (shaded) is approximated by a few rectangles, the Riemann sum idea behind the definite integral.