MathDB
Excentral Triangle Inequality - IMO 1970 - Problem 15.

Source:

May 24, 2011
inequalitiesgeometrycircumcircleperimetertrigonometry

Problem Statement

Given △ABC\triangle ABC, let RR be its circumradius and qq be the perimeter of its excentral triangle. Prove that q≤63Rq\le 6\sqrt{3} R. Typesetter's Note: the excentral triangle has vertices which are the excenters of the original triangle.
Back to ProblemsView on AoPS