Vertices lie on the cubic curve y = x^3 + ax^2 + bx + c
Source: IMO ShortList 1991, Problem 22 (USA 4)
August 15, 2008
algebrasquareCubicpolynomialcubic equationIMO Shortlist
Problem Statement
Real constants are such that there is exactly one square all of whose vertices lie on the cubic curve y \equal{} x^3 \plus{} ax^2 \plus{} bx \plus{} c. Prove that the square has sides of length