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From: roberson@ibd.nrc-cnrc.gc.ca (Walter Roberson)
Newsgroups: comp.soft-sys.matlab
Subject: Re: Solve Equation Symbolically
Date: Mon, 12 Nov 2007 21:58:46 +0000 (UTC)
Organization: National Research Council Canada - Conseil national de rechereches Canada
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In article <fhag57$bca$1@fred.mathworks.com>,
evan klinger <eklinger1-nospam@cox.net> wrote:
>Is there a way to increase the 25,000 character limit? I
>really need to solve up to cv12, I just used up to cv3 to
>demonstrate what I'm trying to do. However, using
>solve(collect(expand(cv12))) returns an error:

>??? Error using ==> solve at 162
>Unable to find closed form solution.

It isn't any 25000 character limit that is getting you:
you are trying to find the closed form solution to a polynomial
of order 12 that does not happen to be factorable down
to polynomials of degree 5 or less (degree 5 is the maximum
for which closed form polynomial solutions always exist.)

Using Maple directly, there is simply no closed form solution
available for cv12. Beyond cv3, even where the closed form
solutions exist in principle, Maple will just show a generalized
placeholder instead (closed form quadratics and quintics are
pretty messy at the best of times.)
-- 
  "Is there any thing whereof it may be said, See, this is new? It hath
  been already of old time, which was before us."    -- Ecclesiastes