log(a^n)M
=loga(M)/loga(a^n)
=loga(M)/n
即log(a^n)M=1/n×log(a) M
换底公式loga(b)=logx(b)/logx(a)这里是以x为底换的
我做的时log(a^n)M它意a为底数换的即loga(a^n)/loga(M)
懂了没