SOLUTION: Find sin2x, cos 2x, and tan 2x if cos x= 1/sqrt 10 and x terminates in quadrant IV. sin 2x = _______ cos 2x = ______ tan 2x = ______

Algebra ->  Trigonometry-basics -> SOLUTION: Find sin2x, cos 2x, and tan 2x if cos x= 1/sqrt 10 and x terminates in quadrant IV. sin 2x = _______ cos 2x = ______ tan 2x = ______      Log On


   

Question 1074682: Find sin2x, cos 2x, and tan 2x if cos x= 1/sqrt 10 and x terminates in quadrant IV.
sin 2x = _______
cos 2x = ______
tan 2x = ______
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Find sin(2x), cos(2x), and tan(2x) if cos(x) = 1/sqrt 10 and x terminates in quadrant IV.
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I can do that.
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cos(t) = 1/sqrt(10)
sin%28t%29+=+sqrt%281+-+cos%5E2%28t%29%29+=+-3sqrt%2810%29%2F10 *** sin negative in Q4 ***
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sin(2t) = 2sin(t)cos(t) = -3/5
cos(2t) = sqrt(1 - sin^2(2t)) = -4/5
tan = sin/cos = 3/4
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sin 2x = _______
cos 2x = ______
tan 2x = ______