SOLUTION: Prove the identity of (sin4x-cos4x)/(1-cot4x)=sin4x

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Question 1204772: Prove the identity of (sin4x-cos4x)/(1-cot4x)=sin4x
Answer by ikleyn(52814) About Me  (Show Source):
You can put this solution on YOUR website!
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Prove the identity of (sin4x-cos4x)/(1-cot4x)=sin4x
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  %28sin%284x%29-cos%284x%29%29%2F%281-cot%284x%29%29 = %28sin%284x%29-cos%284x%29%29%2F%281-cos%284x%29%2Fsin%284x%29%29 = %28sin%284x%29-cos%284x%29%29%2F%28%28sin%284x%29-cos%284x%29%29%2F%28sin%284x%29%29%29 = 

          cancel common factors (sin(4x)-cos(4x)).  You will get then

= sin(4x).


QED.

Solved.