SOLUTION: find the exact value of the expression: sin(-11(pi)/12)

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Question 301151: find the exact value of the expression:
sin(-11(pi)/12)

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
find the exact value of the expression:
sin(-11(pi)/12)
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(-11/12)pi = -165 degrees
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sin(-165 degree) = - sin(15 degrees)
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= -sin(60-45)
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= -[sin(60)cos(45)-cos(60)sin(45)]
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= -[sqrt(3)/2*sqrt(2)/2 - (1/2)(sqrt(2)/2]
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= -[sqrt(6)/4 - sqrt(2)/4]
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= -[sqrt(6)-sqrt(2)]/4
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Cheers,
Stan H.