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信息发布者:
$ (a-b)^2(a+b)^2$
3
5或10
$解:最简公分母为:(a+2b)(a-2b)$
$\frac {a+b}{(a+2b)(a-2b)}、-\frac {a+b}{(a+2b)(a-2b)}$
$解:最简公分母为2(a-2)^2$
$\frac {2a}{2(a-2)^2}、\frac {b}{2(a-2)^2}、\frac {c(a-2)}{2(a-2)^2}$
$解:最简公分母为6(3m+5n)(3m-5n)$
$\frac {4m(3m-5n)}{6(3m+5n)(3m-5n)}、\frac {9n(3m+5n)}{6(3m+5n)(3m-5n)}、$
$\frac {-6(2m+5)}{6(3m+5n)(3m-5n)}$
$解:最简公分母为(x-y)(x+y)^2$
$\frac {x(x+y)^2}{(x-y)(x+y)^2}、\frac {y(x-y)}{(x-y)(x+y)^2}、- \frac {2(x+y)}{(x-y)(x+y)^2}$
$解:由题意得a=x-1,b=3(x+1)(x-1)$
$∵\frac ba=-6$
$∴\frac {3(x+1)(x-1)}{x-1}=-6,即3(x+1)=-6$
$解得x=-3$
$∴\frac 1{3x^2-3}=\frac 1{3×(-3)^2-3}=\frac 1{24},\frac 2{x-1}=\frac 2{-3-1}=-\frac 12$
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