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Any triangle, Trigonometric function - second episode! (Posted on 2007-11-18)

Prove that in any triangle cos(A)+cos(B)+cos(C)>1

See The Solution Submitted by Chesca Ciprian

Rating: 3.0000 (1 votes)

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re: Solution

| Comment 9 of 12 |

(In reply to Solution by Praneeth)

Very nice! I would never had thought of 'c = a*cosB + b*cosA', but I do see how that follows from the law of cosines.

Posted by Brian Smith on 2007-11-20 12:03:23

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