SOLUTION: How do i find the exact value of the product cos[5pi/24] sin[11pi/24]

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Question 875407: How do i find the exact value of the product
cos[5pi/24] sin[11pi/24]
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
How do i find the exact value of the product
cos[5pi/24] sin[11pi/24]
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Identity: sin%28s%29cos%28t%29=%281%2F2%29%28sin%28s%2Bt%29%2Bsin%28s-t%29%29
sin[11pi/24]cos[5pi/24]=
..
calculator check:
set calculator to radians
cos[5pi/24]* sin[11pi/24]≈0.786566
exact value as calculated=(√3+√2)/4≈0.786566