Polynomial functional equation!
Source: Iran TST 2012-Second exam-1st day-P2
May 12, 2012
algebrapolynomialfunctionalgebra proposed
Problem Statement
Let be a polynomial of degree at least with all of its coefficients positive. Find all functions such that
f(f(x)+g(x)+2y)=f(x)+g(x)+2f(y) \forall x,y\in \mathbb R^+.Proposed by Mohammad Jafari