题目是否如下所示：
(x^2+xy)分之(x-y) 除以(x^2y^2-x^4)分之(xy-x^2)*(x-y)分之1
=[x(x+y)分之(x-y) 乘以 [x(y-x)]分之x²(y²-x²) 乘以 (x-y)分之1
= - (x+y)分之(y²-x²) 乘以(x-y)分之1
= - (x+y)分之(y+x)(y-x) 乘以 (x-y)分之1
=1非常感谢