ab=1,求1/a+1 + b/b+1的值

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ab=1,求1/a+1 + b/b+1的值

ab=1,求1/a+1 + b/b+1的值
ab=1,求1/a+1 + b/b+1的值

ab=1,求1/a+1 + b/b+1的值
1/(a+1) + b/(b+1)
=(b+1+ab+b)/(ab+a+b+1)
=(ab+a+b+1)/(ab+a+b+1)
=1

答案好像是 b+3 吧

若b≠ -1
1/(a+1) + b/(b+1)
=(b+1+ab+b)/(ab+a+b+1)
=(1+2b+ab)/((a+1)(b+1))
=2*(1+b)/((a+1)(b+1))
=2/(a+1)
若b=-1

1/(a+1) + b/(b+1)
=(b+1+ab+b)/(ab+a+b+1)
=(1+2b+ab)/((a+1)(b+1))
=2*(1+b)/((a+1)(b+1))