x3-y3-x2+2xy-y2 因式分解
问题描述：
x3-y3-x2+2xy-y2 因式分解
答
x3-y3-x2+2xy-y2
=(x-y)(x^2+xy+y^2)-(x-y)^2
=(x-y)(x^2+xy+y^2-x+y)