MathDB
Inequality

Source: Greece National Olympiad 2002 , Seniors , Problem 1.

November 18, 2005
inequalitiesquadraticsanalytic geometryinequalities proposed

Problem Statement

The real numbers a,b,ca,b,c with bc0bc\neq0 satisfy 1c2bc0.\frac{1-c^2}{bc}\geq0. Prove that 10(a2+b2+c2bc3)2ab+5ac.10(a^2+b^2+c^2-bc^3)\geq2ab+5ac.