MathDB
Too easy to be in a mathematical competition surely...

Source: Pan African Olympiad 2008

October 1, 2011
inequalitiesrearrangement inequalityinequalities proposed

Problem Statement

Let xx and yy be two positive reals. Prove that xyxn+2+yn+2xn+ynxy\le\frac{x^{n+2}+y^{n+2}}{x^n+y^n} for all non-negative integers nn.