SOLUTION: Use the power - reduction formula to find the exact value of sin ( pi/12)

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Question 1011315: Use the power - reduction formula to find the exact value of sin ( pi/12)
Found 2 solutions by ikleyn, stanbon:
Answer by ikleyn(52847) About Me  (Show Source):
You can put this solution on YOUR website!
.
pi%2F12 = 180%2F12 = 15°.

sin(15°) = sqrt%282-sqrt%283%29%29%2F2.

See the lesson Trigonometric functions of half argument - Examples in this site.


Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Use the power - reduction formula to find the exact value of sin ( pi/12)
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sin(pi/12) = sin((1/2)(pi/6)) = sqrt[(1-cos(pi/2))/2]
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= sqrt[(1-sqrt(3)/2)/2]
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= sqrt[(2-sqrt(3))/4]
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= sqrt[(1/2) - (sqrt(3)/4]
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Cheers,
Stan H.
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