SOLUTION: exact value of cos^2 15 degrees - sin^2 15 degrees

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Question 866473: exact value of cos^2 15 degrees - sin^2 15 degrees
Answer by lwsshak3(11628) About Me  (Show Source):
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exact value of cos^2 15 degrees - sin^2 15 degrees
Identity: cos(2x)=cos^2(x)-sin^2(x)
cos^2 15 degrees - sin^2 15 degrees=cos(30)=√3/2