equifacial tetrahedron and circumcircles of faces
Source: RMO District 2005, 8th Grade, Problem 3
March 5, 2005
geometry3D geometrytetrahedroncircumcircletrigonometrytrig identitiesLaw of Sines
Problem Statement
Prove that if the circumcircles of the faces of a tetrahedron have equal radii, then , and .