platonic solid

• 由全等的正多边形面组成、且每个顶点处相交的面数相同的凸多面体。这样的正多面体恰好有五种：正四面体、正六面体（立方体）、正八面体、正十二面体和正二十面体。

A convex polyhedron with identical regular polygon faces and the same number of faces meeting at each vertex. There are exactly five such shapes: tetrahedron, cube, octahedron, dodecahedron, and icosahedron.

1. Regular polyhedronC1formal

   A convex polyhedron with identical regular polygon faces and the same number of faces meeting at each vertex. There are exactly five such solids: tetrahedron, cube, octahedron, dodecahedron, and icosahedron.

   正多面体

   • The tetrahedron is the simplest platonic solid, with four triangular faces.
   • Ancient Greek philosophers associated platonic solids with the classical elements.
   • A cube is a platonic solid because all its faces are identical squares.