perplexus.info :: Just Math : Trigonometric Fun

Trigonometric Fun (Posted on 2004-12-06)

Show that cos(π/7) - cos(2π/7) + cos(3π/7) = 1/2.

See The Solution Submitted by SilverKnight

Rating: 3.6667 (3 votes)

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re(2): Arbitrary Evaluation

| Comment 5 of 7 |

(In reply to re: Arbitrary Evaluation by Charlie)

Oh, my gosh, of course. Thank you, Charlie. Hugs. -CeeAnne-

Posted by CeeAnne on 2004-12-06 23:34:53

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