[(-2y+x)(x+2y)-(x-2y)^2+8y*(x+y)]/4x

问题描述:

[(-2y+x)(x+2y)-(x-2y)^2+8y*(x+y)]/4x
过程!

原式=[x^2-(2y)^2-x^2+4xy-4y^2+8xy+8y^2]/4x
=[x^2-x^2+8y^2-8y^2+12xy]/4x
=12xy/4x
=3y