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Logs with Different Bases


Date: 11/26/97 at 11:39:33
From: kevin
Subject: Logs

How do you do an addition problem involving logs with different bases?

Date: 11/26/97 at 15:40:18
From: Doctor Rob
Subject: Re: Logs

Probably by converting them to a single base.  The conversion
equation is:

   log_a(x) = log_b(x)*log_a(b)

If you know the two bases explicity, the last log above is a constant 
you can calculate, and then you have replaced a log to the base a with 
a log to the base b.

-Doctor Rob,  The Math Forum
 Check out our web site!  http://mathforum.org/dr.math/

Associated Topics:
High School Exponents

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