`intsin3xcos^2xdx`

Explanation

`intsin3xcos^2xdx`
=`intsin3x.(1+cos2x)/2dx`
=`1/2 int{sin3x+sin3x.cos2xdx}`
=`1/2intsin3x+1/4 int2.sin3x.cos2x.dx`
=-1/6cos3x+`1/4 int(sin5x+sinx)dx`
=-1/6cos3x-1/20cos5x-1/4cosx+C