证明:log(a)M*log(b)N=log(a)N*log(b)M.对调真数的位置,对数的积不变.
问题描述:
证明:log(a)M*log(b)N=log(a)N*log(b)M.对调真数的位置,对数的积不变.
答
log(a)M*log(b)N
=lgM/lga*lgN/lgb
=(lgM/lgb)*(lgN/lga)
=log(a)N*log(b)M