계산 적분 8747°(x*sin2x)dx

계산 적분 8747°(x*sin2x)dx

지부 적분
∫(x*sin2x)dx
=(1/2)∫(x*sin2x)d2x
=-(1/2)∫x*dcos2x
=-(1/2)xcos2x+(1/2)∫cos2xdx
=-(1/2)xcos2x+(1/4)∫cos2xd2x
=-(1/2)xcos2x+(1/4)sin2x+C