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Author Comment/Response
yehuda ben-shimol
10/31/04 00:23am

Hi,
If you use simplification (as already given in previouse answers to your post)
Simplify[2 Log[a, x] - Log[a, (x - 1)] == Log[a, (x - 2)]]
you get
(Log[-2 + x] + Log[-1 + x] - 2*Log[x])/Log[a] == 0
so the solution depends only on the numerator and involves only natural log (no "a" in the numerator)
Plot the numerator and easily see that the numerator approaches the x axis from below (actually they meet at infinity).
but forr all practical purposes a large enough number will do.
for other cases where you may have a finite solution, after simplifying as mentioned befor, you may use numerical solution with FindRoot
FindRoot["the numerator of the simplified expression",{x,x0}]
where x0 is a starting value
yehuda

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Subject (listing for 'Solving Log Equations')
Author Date Posted
Solving Log Equations buffer 09/01/04 10:39pm
Re: Solving Log Equations Andrew DuBui... 10/21/04 5:14pm
Re: Solving Log Equations Paul Stysley 10/27/04 1:46pm
Re: Solving Log Equations KENZOU 10/30/04 5:38pm
Re: Solving Log Equations yehuda ben-s... 10/31/04 00:23am
Re: Solving Log Equations Henry Lamb 10/31/04 11:52pm
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