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2017 Polish Junior Math Olympiad Finals P1

Source: 2017 Polish Junior Math Olympiad Finals

May 22, 2023
number theory

Problem Statement

Let aa, bb, and cc be positive integers for which the number a2+bb2+c\frac{a\sqrt2+b}{b\sqrt2+c} is rational. Show that the number ab+bc+caab+bc+ca is divisible by a+b+ca+b+c.