SOLUTION: use pi/3 + pi/4=7pi/12 find the exact value of sin 7pi/12

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Question 285553: use pi/3 + pi/4=7pi/12 find the exact value of sin 7pi/12
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
use pi/3 + pi/4=7pi/12 find the exact value of sin 7pi/12
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sin(pi/3) = 1/2
cos(pi/3) = sqrt(3)/2
sin(pi/4) = sqrt(2)/2
cos(pi/4) = sqrt(2)/2
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sin(A+B) = sin(A)cos(B) + sin(B)cos(A)
sin(7pi/12) = 1/2*sqrt(2)/2 + sqrt(3)/2*sqrt(2)/2
= sqrt(2)/4 + sqrt(6)/4
= %28sqrt%282%29+%2B+sqrt%286%29%29%2F4