u=sin(2x)
du=2cos(2x)dx
1/2du=cos(2x)dx
integral( u (1/2) du )=(1/2) integral ( u du )(=1/2) (1/2)u^2 + C=(1/4)u^2 + C
u=sin(2x) di ==>(1/4) sin^2(2x) + C bulunur.