Is the star tetrahedron a Platonic solid?
Is the star tetrahedron a Platonic solid? The dual of every Platonic solid is another Platonic solid, so that we can arrange the five solids into dual pairs. The tetrahedron is self-dual (i.e. its dual is another tetrahedron). The cube and the octahedron form a dual pair. The dodecahedron and the icosahedron form a dual […]