On the occasion of his 65th birthday, we had an interview with

Professor Lars-Erik Persson. We present several questions in this interview

together with his answers. Some of the answers are indeed surprising ...

The Cauchy-Schwarz (C-S) inequality is one of the most famous inequalities in mathematics. In this survey article, we first give a brief history of the inequality. Afterward, we present the C-S inequality for inner product ...