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From: "Alaa Elwany" <alaa_elwany@yahoo.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: (fsolve) + (Scaling): Possibly Simple Problem - Urgent Help Needed
Date: Thu, 10 Nov 2011 18:10:34 +0000 (UTC)
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THANK YOU! WORKED!

Actually, Roger, I do feel stupid now.  I realized what you wrote in this message a few minutes ago, went and tried it, and this idea worked.  
Indeed, just substituting the RHS of Eqn (1) into Eqn (2) was sufficient, and fsolve seems to be having much less trouble with that.

Thank you very much Roger.  That was a very simple, yet efficient, resolution.  I feel bad because I should have thought about it myself, but you know, sometimes when you delve too deep into a problem, you miss very evident and simple resolutions like what happened with me now!!!! That's why it's useful to have a second opinion.

Thanks again for you and for all the participants in this thread.

Cheers!

"Roger Stafford" wrote in message <j9gue6$3td$1@newscl01ah.mathworks.com>...
> "Alaa Elwany" <alaa_elwany@yahoo.com> wrote in message <j9gmdq$54r$1@newscl01ah.mathworks.com>...
> > Your idea is certainly the most valid one, but unfortunately I did make a mistake and did not realize that E is itself a power function of x(2)! .......
> - - - - - - - - -
>   Even so, you could still substitute the right hand side of the first equation in place of x1 in the second equation and obtain an equation involving only x2, which ought to give you far less difficulties than you are experiencing at present.  Your first equation would then allow you to determine x1 after x2 was solved.
> 
> Roger Stafford