Question 1056791: Find sin (2x), cos(2x), and tan(2x) from the given information.
Write your answer as a fraction.
tan(x) = -1/3, x in quadrant IV
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! Find sin (2x), cos(2x), and tan(2x) from the given information.
Write your answer as a fraction.
tan(x) = -1/3, x in quadrant IV
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In Q4 a terminal point is (1,-3)
x = 1, y = -3
r = sqrt(x^2 + y^2) = sqrt(10)
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sin(x) = y/r = -3/sqrt(10)
cos(x) = x/r = 1/sqrt(10)
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sin(2x) = 2sin(x)(cos(x) = -6/10 = -3/5 --> Q4
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cos(2x) = sqrt(1 - sin^2(2x)) = 4/5
tan(2x) = sin/cos = -3/4
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