Question 783222
Find the exact values of cosθ, and tanθ 
given sin&#952;=-(sqrt3)/2 and cos&#952;<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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