因式分解的简单应用 (21 18:50:51)

1.（x2+2xy+y2)/(x+y) =(x+y)^2/(x+y)=x+y
2.[(a-b)2+2(b-a)]/(a-b) = (a-b)-2
3.(ab2+a2b)/(a+b)=ab(b+a)/(a+b)=ab
4.(x2-49)/(7-x) =(x-7)(x+7)/(7-x)=-(x+7)
5.(4mn3+6m3n)/(2n2+3m2)=2mn(2n^2+3m^2)/(2n^2+3m^2)=2mn
6.[(2a-1)2-(3a-1)2]/(5a-2)=[(2a-1+3a-1)(2a-1-3a+1)]/(5a-2)=-a