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回复(1) 2010-05-16 09:31 来自版块 - 
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teacher2解答:给你个思路 f(-x)+f(x+1) =1/[2^(-x)+√2]+1/[2^(x+1)+√2] =2^x/(1+√2*2^x)+(√2/2)(√2*2^x+1) =(2^x+√2/2)/(√2*2^x+1) =√2/2。(2010-05-16 10:20)

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