MathDB
any convex polyhedron has three edges that can be used to form a triangle.

Source: 2009 Oral Moscow Geometry Olympiad grades 10-11 p5

September 14, 2020
convexgeometrypolyhedron

Problem Statement

Prove that any convex polyhedron has three edges that can be used to form a triangle.
(Barbu Bercanu, Romania)