(x-y+4xy/x+y)(x+y-4xy/x+y)等于的多少? 谢谢!

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(x-y+4xy/x+y)(x+y-4xy/x+y)等于的多少?谢谢!(x-y+4xy/x+y)(x+y-4xy/x+y)等于的多少?谢谢!(x-y+4xy/x+y)(x+y-4xy/x+y)等于的多

(x-y+4xy/x+y)(x+y-4xy/x+y)等于的多少? 谢谢!
(x-y+4xy/x+y)(x+y-4xy/x+y)等于的多少? 谢谢!

(x-y+4xy/x+y)(x+y-4xy/x+y)等于的多少? 谢谢!
原式=[(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)
=x²-y²

[(x+y)+(4xy/x-y)][(x+y)-(4xy/x-y)]和
(a+b)(a-b) 一样