因:8^a=9 即2^(3a)=9,可得:log2(9)=3a
2^b=5 即:log2(5)=b
log9(125)=log2(9)/log2(125)
=3a/3log2(5)
=3a/3b
=a/b
若8的a次方=9,2的b次方=5,则log以9为底125的对数=?
若8的a次方=9,2的b次方=5,则log以9为底125的对数=?
数学人气:113 ℃时间:2019-10-19 15:30:38
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