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Re: Exponential Equations

• To: mathgroup at smc.vnet.net
• Subject: [mg28799] Re: [mg28792] Exponential Equations
• From: BobHanlon at aol.com
• Date: Sun, 13 May 2001 03:28:47 -0400 (EDT)
• Sender: owner-wri-mathgroup at wolfram.com

Depending on which version you have, one or both of these will work

Select[Solve[3^(2 x)==(1/9)^(x + 5),x], Element[x /. #, Reals]&]//FullSimplify

Select[Solve[3^(2 x)==(1/9)^(x + 5),x], FreeQ[x /. #, Complex]&]//FullSimplify


Bob Hanlon

In a message dated 2001/5/12 9:48:40 PM, PLarson at bju.edu writes:

>Why can't Mathematica find x = -5/2 when executing the following? Is
>there a package I should load? It seems so simple.
>
>Solve[3^(2 x)==(1/9)^(x + 5),x]
>