怎么化简（x-y+4xy/x-y）（x+y-4xy

1个回答

原式= [(x-y)^2/(x-y) + 4xy/(x-y)] [(x+y)^2/(x+y) - 4xy/(x+y)]
= {[(x-y)^2 + 4xy]/(x-y)}{[(x+y)^2 - 4xy]/(x+y)}
=[(x+y)^2/(x-y)][(x-y)^2/(x+y)]
=(x+y)(x-y)
=x^2 - Y^2