MathDB
Romania District Olympiad 2001 - Grade IX

Source:

March 12, 2011
functioninductionalgebra proposedalgebra

Problem Statement

Consider a function f:ZZf:\mathbb{Z}\to \mathbb{Z} such that:
f(m2+f(n))=f2(m)+n, m,nZf(m^2+f(n))=f^2(m)+n,\ \forall m,n\in \mathbb{Z}
Prove that:
a)f(0)=0f(0)=0; b)f(1)=1f(1)=1; c)f(n)=n, nZf(n)=n,\ \forall n\in \mathbb{Z}
Lucian Dragomir