记p=lg(1/3)^lg2*2^lg30,求p的值,要求详解,

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记p=lg(1/3)^lg2*2^lg30,求p的值,要求详解,
记p=lg(1/3)^lg2*2^lg30,求p的值,要求详解,

记p=lg(1/3)^lg2*2^lg30,求p的值,要求详解,
是 p =(1/3)^(lg2) *2^(lg30) 吗?
= = = = = = = = =
因为 p =(1/3)^(lg2) *2^(lg30) ,
两边取对数, 得
lg p =(lg2) *lg(1/3) +(lg30) *(lg2)
=(lg2) *( -lg3) +(1+lg3) *(lg2)
=lg2,
所以 p =2.
= = = = = = = = =
说明:
(1) xy (x乘以y) 取对数后变成 lg x +lg y.
(2) x^y (x的y次方) 取对数后变成 y lg x.
即 幂变乘, 乘变加.

取指数