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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: Arbitrary Evaluation

| Comment 3 of 7 |

(In reply to by )

Because of the font used, the symbol for pi, used in the puzzle, can look like the lower case of the letter N, but it's not: it's pi.

Posted by Charlie on 2004-12-06 21:34:51

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