设x=1/(log以1/2为底的1/3的对数）+1/(log以1/5为底的1/3）,则x∈?_数学解答

设x=1/(log以1/2为底的1/3的对数）+1/(log以1/5为底的1/3）,则x∈?

人气：128 ℃　时间：2020-04-08 07:35:06

解答

X=1/(LOG(1/2,1/3)+1/(LOG(1/5,1/3)
=LG(1/2)/LG(1/3)+LG(1/5)/LG(1/3)
=(LG(1/2)+LG(1/5))/LG(1/3)=LG((1/2)*(1/5))/LG(1/3)
=-1/LG(1/3)