Hi all, I have a maths test on Tuesday at University, and I have a practice test. One of the questions I cannot find the solution to in my notes, it is: Integrate (Cos[2x])^3, that is, Cos2x all cubed. I don't see how to go about this problem and it is really starting to bug me! My notes only have examples for stuff like 'Sinx^3' integrate, but not with the '2x' just x. Any help is greatly appreciated. Apparently the answer should be: 1/24 (9Sin2x + Sin6x).