化简(x^2+xy)\(x^2-xy)÷(x+y)÷(-xy)\(y^2-xy)的结果是?

化简(x^2+xy)\(x^2-xy)÷(x+y)÷(-xy)\(y^2-xy)的结果是?
化简(x^2+xy)\(x^2-xy)÷(x+y)÷(-xy)\(y^2-xy)的结果是?

化简(x^2+xy)\(x^2-xy)÷(x+y)÷(-xy)\(y^2-xy)的结果是?
(x^2+xy)\(x^2-xy)÷(x+y)÷(-xy)\(y^2-xy)
=x(x+y)/x(x-y)×1/(x+y)×y(x-y)/xy
=1/x