不等式1/2^x-1>1/1-2^x-1的解集为
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不等式1/2^x-1>1/1-2^x-1的解集为
不等式1/2^x-1>1/1-2^x-1的解集为
不等式1/2^x-1>1/1-2^x-1的解集为
1/(2^x -1)>1/(1- 2^(x-1))
令2^(x-1)=t,则2^x=2*2^(x-1)=2t
∴1/(2t-1)>1/(1-t)
1/(2t-1)+1/(t-1)>0
(3t-2)/[(2t-1)(t-1)]>0
∴t>1或t∈﹙1/2,2/3﹚
即2^(x-1)>1或1/2<2^(x-1)<2/3
x-1>0 or -1<x-1<log﹙2﹚﹙2/3﹚
即x>1或0<x<1+log﹙2﹚﹙2/3﹚
亦即0<x<2-log﹙2﹚3或x>1