SOLUTION: Find the exact values of sin 2&#945;, cos 2&#945;, and tan 2&#945; given the following information. cos &#945; = -4/5 90° < &#945; < 180° sin 2&#945; = ? cos 2&#945; = ?

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Question 930587: Find the exact values of sin 2α, cos 2α, and tan 2α given the following information.
cos α = -4/5 90° < α < 180°
sin 2α = ?
cos 2α = ?
tan 2α = ?

Answer by Alan3354(69443)   (Show Source): You can put this solution on YOUR website!
This is all covered in great detail on wikipedia - half angle formulas.

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