SOLUTION: cosx=12/20 quadrant IV find values to cos2x sin2x and tan2x

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Question 883883: cosx=12/20 quadrant IV find values to cos2x sin2x and tan2x
Answer by lwsshak3(11628) About Me  (Show Source):
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cosx=12/20 quadrant IV find values to cos2x sin2x and tan2x
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cosx=12/20=3/5 (working with a (3-4-5) reference right triangle in quadrant IV)
sinx=-4/5
..
cos 2x=cos^2x-sin^2x=9/25-16/25=-7/25
sin2x=2sinxcosx=2*-4/5*3/5=-24/25
tan2x=sin2x/cos2x=24/7