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Thread: Trigonometric formulas urgent help needed

  1. October 6th 2005, 10:25 AM #1
    LoB
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    Trigonometric formulas urgent help needed

    Cos( 180/7 )* Cos( (4 *180)/7) * Cos( (5*180)/7)

    Could anyone help me with this one? I just probably don't know some formula, but google doesn't help me to it
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  2. October 6th 2005, 04:35 PM #2
    hpe
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    Quote Originally Posted by LoB
    Cos( 180/7 )* Cos( (4 *180)/7) * Cos( (5*180)/7)

    Could anyone help me with this one? I just probably don't know some formula, but google doesn't help me to it
    Use the product identity for the cosine.
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