2 circles of family of circles with dictance of centers <=R\sqrt3
Source: Rioplatense 1996 L3 P1
September 19, 2022
geometrycombinatoricscombinatorial geometry
Problem Statement
Given a family of circles of the same radius , which completely covers the plane (that is, every point in the plane belongs to at least one circle of the family), prove that there exist two circles of the family such that the distance between their centers is less than or equal to .