If y = 1/2 log (1-cos 2x / 1 + cos 2x), prove that dy/dx = 2 cosec 2x Share with your friends Share 11 Rishabh Mittal answered this y=12 log 1-cos 2x1 + cos 2x =12 log 2 sin2x2 cos2x=12 log tan2x =log tan2x12=logtan xy= log tan xOn differentiating both sides wrt x , we gety'=1tan xsec2x=cos xsin x1cos2x =1sin x cos x=22 sin x cos x =2sin 2x=2 cosec 2x Hence Proved 28 View Full Answer