Source: Regional Olympiad - Federation of Bosnia and Herzegovina 2012
September 25, 2018
algebraidentityvalue
Problem Statement
Find all possible values of a1(b1+c1+b+c1)+b1(c1+a1+c+a1)+c1(a1+b1+a+b1)−a+b+c1(a1+b1+c1+a+b1+b+c1+c+a1)+a21+b21+c21 where a, b and c are positive real numbers such that ab+bc+ca=abc