MathDB
Socialists Republic Of Czechoslovakia 7

Source: IMO LongList 1959-1966 Problem 41

September 2, 2004
geometrypolygoncountingObtuse triangleIMO LonglistIMO Shortlist

Problem Statement

Given a regular nn-gon A1A2...AnA_{1}A_{2}...A_{n} (with n≥3n\geq 3) in a plane. How many triangles of the kind AiAjAkA_{i}A_{j}A_{k} are obtuse ?
Back to ProblemsView on AoPS