A point inside a regular tetrahedron T of unit volume
Source: IMO ShortList 1990, Problem 19 (POL 1)
August 15, 2008
geometry3D geometrytetrahedroncombinatoricsIMO Shortlist
Problem Statement
Let be a point inside a regular tetrahedron of unit volume. The four planes passing through and parallel to the faces of partition into 14 pieces. Let be the joint volume of those pieces that are neither a tetrahedron nor a parallelepiped (i.e., pieces adjacent to an edge but not to a vertex). Find the exact bounds for as varies over