谁帮我化简：[(x+y)(x-y)-(x+y)^2-2y(x-y)-2xy]÷xy
问题描述：
谁帮我化简：[(x+y)(x-y)-(x+y)^2-2y(x-y)-2xy]÷xy
答
原式=(x^2-y^2-x^2-2xy-y^2-2xy+2y^2-2xy)/xy
=(-6xy)/xy
=-6