求解答,一道题 数学
问题描述：
求解答,一道题 数学
x2-x2y+xy2-x+y-y2
(2是平方的意思)
化简分式
答
=x2(1-y)+y2(1-x)-x+y-1+1
=(x2-1)(1-y)+(y2-1)(x-1)
=(x+1)(x-1)(1-y)-(1+y)(1-y)(x-1)
=(x-1)(1-y)(x-y)