SOLUTION: Question--> cos^2(15)-sin^2(15) equals: I know that sin^2(x)+cos^2(x)=1, but am not sure how to manipulate this or other trig identities to find the answer to the question above

Algebra ->  Trigonometry-basics -> SOLUTION: Question--> cos^2(15)-sin^2(15) equals: I know that sin^2(x)+cos^2(x)=1, but am not sure how to manipulate this or other trig identities to find the answer to the question above      Log On


   



Question 1085160: Question--> cos^2(15)-sin^2(15) equals:
I know that sin^2(x)+cos^2(x)=1, but am not sure how to manipulate this or other trig identities to find the answer to the question above.
Thank you in advance!

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
I know that sin^2(x)+cos^2(x)=1, but am not sure how to manipulate this or other trig identities to find the answer to the question
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cos^2(x) - sin^2(x) = cos(2x)