SOLUTION: please prove: sin8(x)=2sin4(x)cos4(x)

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Question 237241: please prove: sin8(x)=2sin4(x)cos4(x)
Answer by rapaljer(4671)   (Show Source): You can put this solution on YOUR website!
You are probably familiar with the double angle formula for sines:


In this case, you have , so use the above formula where you substitute 4x in place of the y:



Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus

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