Geometry 3D

The Icosahedron

The surface of an Icosahedron consists of twenty equilateral triangles and is therefore one of the five Platonic solids.

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

Example:

Given:
  Circumradius rc = 1

Results:   Edge a = 1,0514622
       Apothem h1 = 0,910593
      Altitude h2 = 2
  Circumradius rc = 1
      Inradius ri = 0,79465447
         Volume V = 2,5361507
        Surface S = 9,5745414

See also:

Wikipedia: Platonic solid
eng.matheass.eu