MathDB

2003 National Spain Olympiad, Problem 4

Source: 2003 National Spain Olympiad

June 1, 2017

algebra

Problem Statement

Let

{x}

be a real number such that

{x^3 + 2x^2 + 10x = 20.}

Demonstrate that both

{x}

and

{x^2}

are irrational.