The Octahedron

The Octahedron is a regular four-sided double pyramid. Its surface consists of eight equilateral triangles and is therefore one of the five Platonic solids.

The following elements of a Octahedron are calculated if one of them is given:

• Edge a
• Apothem h₁
• Altitude h₂
• Circumradius r_u
• Inradius r_i
• Volume V
• Surface S

Example:

Given:
¯¯¯¯¯¯
 Circumradius rc = 1

Results:
¯¯¯¯¯¯¯
          Edge a = 1,4142136
  Apothem h1 = 1,2247449
    Altitude h2 = 2
     Inradius ri = 0,57735027
     Volume V = 1,3333333
     Surface S = 6,9282032

See also:

Graphics 3D
Wikipedia: Platonic solid