我又来了哈..分解公因式

问题描述:

我又来了哈..分解公因式
x(x+y)(x-y)-x(x+y)^2

原式=(x+y)(x^2-xy)-(x+y)(x^2+xy)
=(x+y)[x^2-xy-x^2-xy]
=(x+y)(-2xy)