Department of Mathematics, Science Faculty, Selçuk University, 42003 Konya, Turkey
Copyright © 2010 Zübeyde Ulukök and Ramazan Türkmen. This is an open access article distributed under the
Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
We first present an inequality for the Frobenius norm of the Hadamard product of two any square matrices and positive semidefinite matrices. Then, we obtain a trace inequality for products of two positive semidefinite block matrices by using block matrices.