perplexus.info :: Just Math : trigonometry and a triangle

trigonometry and a triangle (Posted on 2004-02-26)

Prove that in a triangle ABC,:

sin(A)sin(B)sin(C) + cos(A)cos(B) = 1

implies:

A = B = 45° and C = 90°.

See The Solution Submitted by mohan

Rating: 2.7143 (7 votes)

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re: solution

| Comment 5 of 15 |

(In reply to solution by jacob)

Very nice.

Posted by Brian Wainscott on 2004-02-26 16:37:05

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