Just to make sure I did it right, everytime I'm ok a differente rule arise
Here is my Question and answer
Find the indefinite integrals of the following functions.
(i)h(u) = cos2(3u)
∫ cos2(3u) du
∫ 1/3 sin2 (3u) = 1/3 sin2 + 3u + c
Thanks again for helping me