Question: Calculate the integral ∫ cos^2(x) dx.
Options:
Correct Answer: (1/2)x + (1/4)sin(2x) + C
Solution:
Using the identity cos^2(x) = (1 + cos(2x))/2, we find that ∫ cos^2(x) dx = (1/2)x + (1/4)sin(2x) + C.