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)

Comments: ( Back to comment list | You must be logged in to post comments.)

re(2): solution

| Comment 10 of 15 |

(In reply to re: solution by Federico Kereki)

w.r.t your comment, in a triangle, all sines are positive.

Posted by mohan on 2004-02-29 03:08:26

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