两边乘2就行。前者2log2 3=log2 9＞log2 8=3。后者2×2^(1/3)=2^(1/3+1)<2^(1/2+1)=2根号2<3。于是log2 3＞2的1/3次方。
log(2,3) 2^(1/3)log(2,3)=lg3/lg2约为0.477/0.3约为1.591.59³>2，故log(2,3)>2^(1/3)
