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trigonometry and a triangle (Posted on 2004-02-26) Difficulty: 4 of 5
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.)
Some Thoughts re: solution | Comment 6 of 14 |
(In reply to solution by jacob)

sin(a)sin(b)sin(c) <= sin(a)sin(b) only if
sin(a)sin(b)>=0. I like the style of the
proof, but this should be fixed.
  Posted by Federico Kereki on 2004-02-27 06:43:35

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