MathDB
Nordic MC 2008 Q1

Source:

March 3, 2013
functionalgebra unsolvedalgebra

Problem Statement

Find all reals A,B,CA,B,C such that there exists a real function ff satisfying f(x+f(y))=Ax+By+Cf(x+f(y))= Ax+By+C for all reals x,yx,y.