(1)先求S(sin2x)^2dx=x/2-(1/4)sina2xcos2x

　　S(sin2x)^2dx=-(1/2)Ssin2xdcos2x

　　=-(1/2){sin2xcos2x-2Scos2xcos2xdx}

　　=-(1/2){sin2xcos2x-2S(1-(sinx)^2)dx}

　　=-(1/2)sin2xcos2x+S(1-(sinx)^2)dx

　　=-(1/2)sin2xcos2x+x-S((sinx)^2)dx

　　S(sin2x)^2dx=-(1/4)sin2xcos2x+(1/2)x

　　(2)S(sinx)^4dx=-S(sinx)^3dcosx

　　=-(sinx)^3cosx+3Scos^2xsin^2xdx

　　=-(sinx)^3cosx+(3/4)S4cos^2xsin^2xdx

　　=-(sinx)^3cosx+(3/4)Ssin^22xdx

　　=-(sinx)^3cosx+(3/4)(x/2-(1/4)sina2xcos2x)

　　下面自己整理吧