SOLUTION: PLEASE help prove the identity? (1-cos2x)/tanx = sin2x

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Question 644034: PLEASE help prove the identity?
(1-cos2x)/tanx = sin2x
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
%281-cos2x%29%2Ftanx+=+sin2x
start with left side and prove it's equal to right side

%281-cos2x%29%2Ftanx+ ....use identity 1%2Ftan%28x%29=ctg%28x%29

=%281-cos2x%29ctg%28x%29....use identity cot%28x%29=-%28sin%282x%29%2F%28cos%282x%29-1%29%29

=%281-cos2x%29%2A%28-%28sin%282x%29%2F%28cos%282x%29-1%29%29%29....pull -1 in front of %281-cos2x%29

=%281-cos2x%29%2A%28-%28sin%282x%29%2F%28-%281-cos%282x%29%29%29%29%29

=%281-cos2x%29%2A%28sin%282x%29%2F%281-cos%282x%29%29%29%29

=cross%28%281-cos2x%29%29%2A%28sin%282x%29%2Fcross%28%281-cos%282x%29%29%29%29%29

=sin%282x%29.....we arrived to the right side of your identity and it proves your identity