1. The problem statement, all variables and given/known data I just need to find the anti-derivative of this equation: [itex]\int x(sin^2(3x)cos(3x))dx[/itex] 2. Relevant equations [itex]sin^2(x)+cos^2(x)=1[/itex] 3. The attempt at a solution I'm not really sure where to start here. I tried to do a substitution first but couldn't make it work. So then I tried to put sin^2 in terms of cos^2 but that didn't seem to help me out any more. Anyone have an idea of how to tackle this problem? Thanks in advance!