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From: "Bruno Luong" <b.luong@fogale.findmycountry>
Newsgroups: comp.soft-sys.matlab
Subject: Re: eigenvalues
Date: Sat, 7 Nov 2009 07:31:30 +0000 (UTC)
Organization: FOGALE nanotech
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> 
> dear all,
> any suggestion plz...

Yes: drop trying to compute symbolic eigenvalues for matrix of 40 in size. You might get - if -ever - a formula that not fits on 1000 pages of paper. Before you will be asked what to do with it, might be you might think about saving a tree not to print out such formula.

Now the chance that Matlab or any software that can solve for eigenvalues problem for you is zero. You might know that this problem is equivalent to finding the roots of 40th order polynomials. Take a look at Galois's theory, who has shown two centuries ago that - in general - such formula does not exist for polynomial or order 5th or greater, e.g. 40th order.

Bruno