1函数y=log2^x+log(2x)的值域是 2等比数列a+log2^3,a+log4^3,a+log16^3的公比是

问题描述:

1函数y=log2^x+log(2x)的值域是 2等比数列a+log2^3,a+log4^3,a+log16^3的公比是
y=log2^x+logx^(2x)的值域是

一、y=log2^x+logx^(2x)
=log2^x+logx^2+1
=log2^x+1/log2^x+1(换底公式)
令t=log2^x则y=t+1/t+1
所以当x属于(0,1)时,y属于负无穷到-1
当x属于(1,正无穷)时,y属于1到正无穷
二、
a=0 q=1/2