**[solved] trace(A*A) is always positive?**

zeebek

I have a feeling that for any n x n non-trivial matrix A, trace(A*A) is always positive.
Is it true?

zeebek	*[solved] trace(AA) is always positive?** I have a feeling that for any n x n non-trivial matrix A, trace(A*A) is always positive. Is it true?