SOLUTION: What is the simplified form of cos30degrees + (sin210degrees)(cos^2 150degrees)?

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Question 119294: What is the simplified form of cos30degrees + (sin210degrees)(cos^2 150degrees)?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
What is the simplified form of cos30degrees + (sin210degrees)(cos^2 150degrees)?
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cos(30) = [sqrt3]/2
sin(210) = -sin(30) = -1/2
cos(150)= -cos(30)= [-sqrt3]/2
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Your Problem:
{sqrt3]/2 + (-1/2)[[-sqrt3]/2]^2 = [sqrt3]/2 +(-1/2)(3/4)
= [sqrt3]/2 -(3/8)
= 0.8660-0.125
= 0.4910
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Cheers,
Stan H.