SOLUTION: Suppose sinθ = 1/4, and π/2 ≤ θ ≤ 2π. Find the exact value of cos θ. Explain steps please

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Question 858255: Suppose sinθ = 1/4, and π/2 ≤ θ ≤ 2π. Find the exact value of cos θ. Explain steps please
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Suppose sinθ = 1/4, and π/2 ≤ θ ≤ 2π. Find the exact value of cos θ. Explain steps please
Reference angle θ is in quadrant II in which cos<0
use x for θ

calculator check:
sin(x)=1/4
x≈165.52˚
cos(x)=cos(165.52)≈-0.9682…
exact value=-√15/4≈-0.9682…