concurrency in a tetrahedron,
Source: All-Russian MO 2001 Regional (R4) 11.6
September 26, 2024
geometryconcurrencyconcurrenttetrahedron3D geometry
Problem Statement
Prove that if two segments of a tetrahedron, going from the ends of some edge to the centers of the inscribed circles of opposite faces, intersect, then the segments issued from the ends of the crossing with it edges to the centers of the inscribed circles of the other two faces, also intersect.