x根号x+x根号y/xy-y^2)-（x+根号xy+y/x根号x-y根号）y
问题描述：
x根号x+x根号y/xy-y^2)-（x+根号xy+y/x根号x-y根号）y
答
(x√x+x√y)/(xy-y^2)-[x+√(xy)+y]/(x√x-y√y)
=[x(√x+√y)/[y(√x-√y)(√x+√y)]-[x+√(xy)+y]/{(√x-√y)[x+√(xy)+y]}
=x/[y(√x-√y)]-1/(√x-√y)
=(x-y)/[y(√x-√y)]
=(√x-√y)(√x+√y)/[y(√x-√y)]
=(√x+√y)/y