Does anyone know a site that provides an algorithm for finding this(eigenvalues).

What I am trying to do: Compute the eigenvalue(s) of an n x n matrix.


Questions: If lambda = x then det(A-xI)=0, How do I make a matrix multiply and and subtract nonreal numbers in excel. So if I have a 4x4 matrix by using det(A-xI)=0 I will get an equation that looks like ax^4+bx^3+cx^2+dx+e=0 where a, b, c, d, e are some "real numbers". But how do I make excel spit that out? Is this possible in excel?

Alternative ways of producing eigenvalues?

Math is not my issue, I just don't know what excel can and cannot do, and how to do it. YET!