1
Part of 1974 Bundeswettbewerb Mathematik
Problems(2)
Bundeswettbewerb Mathematik 1974 Problem 1.1
Source: Bundeswettbewerb Mathematik 1974 Round 1
10/16/2022
Find the necessary and sufficient condition that a trapezoid can be formed out of a given four-bar linkage.
geometrytrapezoid
25 Points are given on the plane
Source:
9/14/2011
Twenty-five points are given on the plane. Among any three of them, one can choose two less than one inch apart. Prove that there are 13 points among them which lie in a circle of radius 1.
ceiling function