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| Question 783222:  Find the exact values of cosθ, and tanθ given sinθ=-(sqrt3)/2 and cosθ<0
 Answer by stanbon(75887)
      (Show Source): 
You can put this solution on YOUR website! Find the exact values of cosθ, and tanθ given sinθ=-(sqrt3)/2 and cosθ<0
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 If sin and cos are both negative, theta is in QIII
 where both x and y are negative.
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 Since sin = y/r, y = -sqrt(3) and r = 2
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 Then x = sqrt[2^2 - (sqrt(3))^2] = sqrt[1] = 1
 Note: x is negative in QIII
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 Answers:
 cos = x/r = -1/2
 tan = y/x = -sqrt(3)/-1 = sqrt(3)
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 Cheers,
 Stan H.
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