Math
posted by David M. .
Use a half angle formula to determine the exact value of sin 7(pi)/12.

well, 7 pi/6 is 180 + 30 degrees
and 7 pi/6 = twice 7 pi/12
we know sin and cos of 7 pi/6
sin 7 pi/6 = 1/2
cos 7 pi/6 = (1/2)sqrt3
so now you should be able to find the sin of 7 pi/12
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