SOLUTION: Prove using trig identities cos3x=cos^3(x)-3sin^2(x)cos(x) Thank you!

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Question 1151362: Prove using trig identities
cos3x=cos^3(x)-3sin^2(x)cos(x)
Thank you!

Answer by MathLover1(20850)   (Show Source): You can put this solution on YOUR website!



use identity:

write as which is equal to

..........since and we have








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