已知反函数f-1(x)=log2^(1+x)/(1-x)求f(x)的解析式解不等式1-f(X)>1/(4^x-1)
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解:令log2^(1+x)/(1-x)=m,则2^m=(1+x)/(1-x)解之,x=(2^m-1)/(2^m+1)∵f-1(x)=log2^(1+x)/(1-x)∴f(x)=(2^x-1)/(2^x+1)1-f(x)1/(4^x-1)以f(x)代入上式,可以化成2/(2^x+1)>1/(4^x-1)再通分,移项,得:(2*2^x-3)/(4^x-1)>0化成:(2^x+1)(2^x-1)(2^x-1.5)>0解得:2^x>1.5或-1<2^x<1即:x>log(2)1.5或x<0