integral x^2 sin^3(x) dx = 1/108 (-81 (x^2-2) cos(x)+(9 x^2-2) cos(3 x)-6 x (sin(3 x)-27 sin(x)))+constant
As long as you can solve this you will be ok
The first integral is written incorrectly and there should be 4 brackets at the end!!!. Appalled at your inacuracies!
The answer is alpha beta foxtrot!