Source: European Mathematical Cup 2014, Junior Division, Problem 1
December 22, 2014
algebra unsolvedalgebra
Problem Statement
Which of the following claims are true, and which of them are false? If a fact is true you should prove it, if it isn't, find a counterexample.
a) Let a,b,c be real numbers such that a2013+b2013+c2013=0. Then a2014+b2014+c2014=0.
b) Let a,b,c be real numbers such that a2014+b2014+c2014=0. Then a2015+b2015+c2015=0.
c) Let a,b,c be real numbers such that a2013+b2013+c2013=0 and a2015+b2015+c2015=0. Then a2014+b2014+c2014=0.
Proposed by Matko Ljulj