MathDB
easy inequality

Source: Netherlands 1991

June 28, 2009
inequalitiesfunctioninequalities proposed

Problem Statement

Prove that for any three positive real numbers a,b,c, \frac{1}{a\plus{}b}\plus{}\frac{1}{b\plus{}c}\plus{}\frac{1}{c\plus{}a} \ge \frac{9}{2} \cdot \frac{1}{a\plus{}b\plus{}c}.