TOT 115 1986 Spring S3 edges of tetrahedron coincide with vectors, 0 sum?
Source:
August 29, 2019
vectortetrahedronregular tetrahedrongeometry3D geometry
Problem Statement
Vectors coincide with the edges of an arbitrary tetrahedron (possibly non-regular). Is it possible for the sum of these six vectors to equal the zero vector? (Problem from Leningrad)