Posted by **mathstudent** on Friday, January 19, 2007 at 1:19pm.

Prove that if A is a diagonalizable matrix, then the rank of A is the number of nonzero eigenvalues of A.

http://ltcconline.net/greenl/courses/203/MatrixOnVectors/symmetricMatrices.htm

I've read the entire page and while it's on the correct topic, it doesn't prove what I'm looking to prove.