From: <HIDDEN>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Warning: Explicit solution could not be found
Date: Wed, 29 Feb 2012 18:39:12 +0000 (UTC)
Organization: The MathWorks, Inc.
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"Steven_Lord" <> wrote in message <jildb3$j18$>...
> Even substituting in numeric values for some of the variables with SUBS 
> might help SOLVE better handle the equation.
- - - - - - - - -
  Yes, it's a pet peeve of mine that people who present complicated equations to be solved with 'solve' ought to at least consolidate all their "known" parameters into a minimum set.

  In the case of the present equation the parameters, N, a, m, h, so, w, E, and tan(phi) can all be consolidated into just two parameters, a and b, and with the substitution I recommended the equation can be manipulated to become a much shorter

 x^(2^n-1) - (a*x+b)^n = 0.

As such I think it is clear that 'solve' is unlikely to produce an explicit solution to this equation (even if n is a positive integer and it is a polynomial) in terms of the elementary functions it is able to call upon, and in any case it is much easier for whoever undertakes to furnish help on the question to analyze it and explain the difficulties.

Roger Stafford