SOLUTION: Given sin theta=4/11, where pi/2 < theta < pi, find the value of sin 2 theta

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Question 946513: Given sin theta=4/11, where pi/2 < theta < pi, find the value of sin 2 theta
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Given sin theta=4/11, where pi/2 < theta < pi, find the value of sin 2 theta
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x is negative in QII
Since sin = y/r, y = 4 and r = 11
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x = -sqrt[11^2-4^2] = -sqrt(105)
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cos(t) = x/r = -sqrt(105)/11
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sin(2t) = 2*sin(t)(cos(t)) = 2*(4/11)(-sqrt(105)/11)
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Cheers,
Stan H.
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