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Octahedron

Octahedron is one of only five Platonic solids. This is a regular polyhedron with 6 vertices, 12 edges, and 8 faces. All faces are regular triangules and at every vertex meet four faces and four edges.

What if applet does not run?

Drag the mouse to rotate the octahedron. Use the right button to remove and put back individual faces.

(Acknowledgement: I have learned most of Java details from the implementation by Meiko Rachimow.)

The word octahedron originates with the Greek okto (8). The other Platonic solids are tetrahedron, icosahedron, dodecahedron, cube. With 8 faces, 12 edges, and 6 vertices a dodecahedron confirms to the Euler's theorem: 8 - 12 + 6 = 2.

Copyright © 1996-2010 Alexander Bogomolny

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