log(a)b=log(c)b/log(c)a 是怎么推算来的
问题描述:
log(a)b=log(c)b/log(c)a 是怎么推算来的
答
log(a)b=log(c)b/log(c)a把log(c)a乘到左边,变成log(a)b*log(c)a=log(c)b,只要证这个式子就行了.两边都以c为底求幂,c^(log(c)a*log(a)b)=c^(log(c)b),左边=[c^(log(c)a)]^(log(a)b)=a^(log(a)b)=b,右边=c^(log(c)b)...