Functional equation
Source: Swiss Math Olympiad 2010 - final round, problem 6
March 16, 2010
functionalgebra proposedalgebra
Problem Statement
Find all functions such that for all , ,
f(f(x))\plus{}f(f(y))\equal{}2y\plus{}f(x\minus{}y)
holds.
Source: Swiss Math Olympiad 2010 - final round, problem 6