SOLUTION: find exact value of cos pi/12 by using a sum or difference formula

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Question 1158089: find exact value of cos pi/12 by using a sum or difference formula
Found 2 solutions by Shin123, Alan3354:
Answer by Shin123(626) About Me  (Show Source):
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
find exact value of cos pi/12 by using a sum or difference formula
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= cos(15) degs
= cos(45 - 30)
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Wikipedia's "Half angle formulas" covers it well.