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If θ is in Quadrant IV and sinθ = -1/2, then cosθ _____.

User Ganapat
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2 Answers

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Clarification:

The answer is
(√(3) )/(2) (√3/2)

User Raju Singh
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Solution : Quadrant IV ranges from 270 deg to 360 deg Also sinθ = - value & cosθ= + value in IV quadrant Here, sinθ = -1/2, we know sin30=1/2 this gives, θ = 330deg as sinθ = sin(360-θ) Hence, cosθ=cos330=cos(360-30)=cos30 Answer: cos30 = âš3/2
User Scott Veirs
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