tan(36)
http://www.mathisfunforum.com/viewtopic … 87#p378587
The Regular Icosahedron
http://www.mathisfunforum.com/viewtopic.php?id=22966
Note: I was having difficulty making my answer match the one given by Monox D. I-Fly. I have worked out the two versions are the same but I cannot get the final proof to post; why I don't know. So I'll try again later
Base Vectors and Coordinates. A beginning.
http://www.mathisfunforum.com/viewtopic … 53#p387953
A matrix for rotation and the compound angle formulas
http://www.mathisfunforum.com/viewtopic … 28#p389628
Bob
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