Solid mensuration: a modest contribution to a solution 016

Example 016: Radius of sphere circumscribing a regular triangular pyramid

I would like to add a modest contribution to a solution 016.
Radius of inscribbed sphere can be obtained directly (without slope angle determination):

√((AE)^2+(OE)^2 ) = ED-OE → OE = r = ((ED)^2-(AE)^2)/(2*(ED) ) and so on

Best regards !

Matija Oblak

Jhun Vert's picture

This is great. And for convenience of our readers, here is the link:
http://www.mathalino.com/node/1162

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