MathDB
RMO 2016 ,Q2

Source: Oct 23,2016

October 25, 2016
inequalities

Problem Statement

Let a,b,ca,b,c be positive real numbers such that ab1+bc+bc1+ca+ca1+ab=1\dfrac{ab}{1+bc}+\dfrac{bc}{1+ca}+\dfrac{ca}{1+ab}=1. Prove that 1a3+1b3+1c362\dfrac{1}{a^3}+\dfrac{1}{b^3}+\dfrac{1}{c^3} \ge 6\sqrt{2}