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You are not logged in. #1 20070911 06:14:28
finding eigen values in 3x3 symmetrical matrixhow can i go about calculating the eigen values of a 3x3 symmetrical matrix for example: if i do: i end up getting a cubic equation in terms of the eigen value which i don't know how to solve, and im sure there must be a simpler way, if not calculating them, atleast showing that they are more or less than 0 Last edited by lucadeltodesco (20070911 06:17:16) The Beginning Of All Things To End. The End Of All Things To Come. #2 20130927 17:58:25
Re: finding eigen values in 3x3 symmetrical matrixHi;
An oldie but a goodie. You can solve for the roots numerically or by graphing but a more precise idea is to use a Sturm chain. Substitute the endpoints of 0 and infinity. Count the sign changes. We get 3. So we get there are 3 roots between 0 and infinity and since 0 is not a root all 3 are greater than 0. A numerical attack yields: for the three roots. In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. 