以3为底15分之4的对数怎么求

问题描述:

以3为底15分之4的对数怎么求

lg2 = 0.3010,lg3 = 0.4771,lg5 = 0.6990
Log[ 3,4/15] = Log[3,4] - Log[ 3,15]
= 2 Log[3,2] - 1 - Log[3,5]
= 2 lg2 / lg3 - 1 - lg5 / lg3
= (0.6020 - 0.6990) / 0.4771 - 1
= - 1.2033