SOLUTION: Derive a formula for {{{cos3(alpha)}}} in terms of {{{cos(alpha)}}}

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Question 883249: Derive a formula for cos3%28alpha%29 in terms of cos%28alpha%29
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
From a multiple angle formula,
cos%283%2Aalpha%29=4%2A%28cos%28alpha%29%29%5E3-3cos%28alpha%29