Tolong no 11 sama 14 dong. makasih

11, ∫sin²3x dx= ∫(1/2-1/2 cos 6x) dx
                      = ∫1/2 dx- 1/2 ∫cos 6x dx= 1/2-1/2 (1/6 sin6x)= 1/2-1/12 sin 6x