perplexus.info :: Geometry : Cosines everywhere

Cosines everywhere (Posted on 2005-03-21)

Prove that in any triangle ABC, 8.cos(A).cos(B).cos(C) < 1.

See The Solution Submitted by Federico Kereki

Rating: 4.5000 (2 votes)

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probable mistake

Comment 6 of 6 |

needs an "or = to"<BR/>60,60,60<BR/>I hope this is clear.<BR/>

Posted by John on 2006-10-16 01:18:32

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