计算a+b/b-a-b/b

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计算a+b/b-a-b/b

计算a+b/b-a-b/b
计算a+b/b-a-b/b

计算a+b/b-a-b/b
=[(a+b)-(a-b)]/b
=(a+b-a+b)/b
=2b/b
=2

原式=a/(a²-b²)-1/(a+b)÷b/(b-a) =a/[(a+b)(a-b)]-1/(a+b)÷[-b/(a-b)] ...

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原式=a/(a²-b²)-1/(a+b)÷b/(b-a) =a/[(a+b)(a-b)]-1/(a+b)÷[-b/(a-b)] =a/[(a+b)(a-b)]+1/(a+b)×[(a-b)/b] =a/[(a+b)(a-b)]+(a-b)/[b(a+b)] =ab/[b(a+b)(a-b)]+(a-b)²/[b(a+b)(a-b)] =[ab+(a-b)²]/[b(a+b)(a-b)] =(ab+a²-2ab+b²)/[b(a+b)(a-b)] =(a²-ab+b²)/[b(a+b)(a-b)]

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