先化简,再求值 (x²-y²/xy)²÷（x+y）²*(x/x-y)²,其中x=3,y=2
问题描述：
先化简,再求值 (x²-y²/xy)²÷（x+y）²*(x/x-y)²,其中x=3,y=2
答
x=3,y=2(x²-y²/xy)²÷（x+y）²*(x/(x-y)²= (x+y)(x-y)/(xy)² *1/(x+y）² * x²/(x-y)²= y² /{(x+y)(x-y)}= 2² /{(3+2)(3-2)}= 4/5