how to prove cotsquared 2A=(1 + sin 2A)/1-sin2A

Question

how to prove cot squared 2A=(1 + sin 2A)/1-sin2A

Answer 1

Jeff, I think you have an error in your transcription

 

Take a look at this link

 

http://www.numberempire.com/graphingcalculator.php?functions=%281%2Bsin%282*x%29%29%2F%281-sin%282*x%29%29%2C%28cot%282*x%29^2%29&xmin=-3&xmax=3&ymin=-3&ymax=3&var=x

 

I've graphed the left hand side (cot^2(2A)) in yellow and the right hand side in blue.

 

If you have an identity, their graphs have to be identical.