求xsin(2x)的不定积分
问题描述:
求xsin(2x)的不定积分
答
∫ xsin2x dx
= -(1/2)∫ xdcos2x
=-(1/2)xcos2x + (1/2)∫ cos2x dx
=-(1/2)xcos2x + (1/4) sin2x + C