Polyèdre uniforme étoiléEn géométrie, un polyèdre uniforme non convexe, ou polyèdre étoilé uniforme, est un polyèdre uniforme auto-coupant. Il peut contenir soit des faces polygonales non convexes, des figures de sommet non convexes ou les deux. Dans l'ensemble complet des 53 polyèdres étoilés uniformes non prismatiques, il y a les 4 réguliers, appelés les solides de Kepler-Poinsot. Il existe aussi deux ensembles infinis de prismes étoilés uniformes et des antiprismes étoilés uniformes. Ici, nous voyons deux exemples de polyèdres
Grand cubicuboctaèdreIn geometry, the great cubicuboctahedron is a nonconvex uniform polyhedron, indexed as U14. It has 20 faces (8 triangles, 6 squares and 6 octagrams), 48 edges, and 24 vertices. Its square faces and its octagrammic faces are parallel to those of a cube, while its triangular faces are parallel to those of an octahedron: hence the name cubicuboctahedron. The prefix great serves to distinguish it from the small cubicuboctahedron, which also has faces in the aforementioned directions.
Grand rhombicuboctaèdre uniformeIn geometry, the nonconvex great rhombicuboctahedron is a nonconvex uniform polyhedron, indexed as U17. It has 26 faces (8 triangles and 18 squares), 48 edges, and 24 vertices. It is represented by the Schläfli symbol rr{4,} and Coxeter-Dynkin diagram of . Its vertex figure is a crossed quadrilateral. This model shares the name with the convex great rhombicuboctahedron, also called the truncated cuboctahedron. An alternative name for this figure is quasirhombicuboctahedron. From that derives its Bowers acronym: querco.
Cube tronquéIn geometry, the truncated cube, or truncated hexahedron, is an Archimedean solid. It has 14 regular faces (6 octagonal and 8 triangular), 36 edges, and 24 vertices. If the truncated cube has unit edge length, its dual triakis octahedron has edges of lengths 2 and 2 + . The area A and the volume V of a truncated cube of edge length a are: The truncated cube has five special orthogonal projections, centered, on a vertex, on two types of edges, and two types of faces: triangles, and octagons.
