Respostas

2012-12-18T22:59:38-02:00

(x-y):(x-y)2           

(x-y): (x-y)(x-Y)= 1/(x-y)                                                                                                                                                                                                                        

2012-12-19T15:21:03-02:00

Eu axo q eh 4xy ...
Veja...


(x+y)² - (x-y)²

(x+y)(x+y) - (x-y)(x-y)

x² + 2xy + y² - ( x² - 2xy + y ² ) 

x² + 2xy + y² - x² + 2xy - y² 

4xy