MathDB
2015 Azerbaijan IMO TST

Source: 2015 Azerbaijan IMO TST

May 29, 2015
algebrafunction

Problem Statement

Find all functions f:[0,1]Rf:[0,1] \to \mathbb{R} such that the inequality (xy)2f(x)f(y)xy(x-y)^2\leq|f(x) -f(y)|\leq|x-y| is satisfied for all x,y[0,1]x,y\in [0,1]