Question 275502
tan 2x = sin 2x/cos 2x=( 2 sin x cos x)/(cos^2 x- sin^2 x) Divide by sin^2 x
=( 2 cos x/ sin x)/(cos^2x/sin^2 x) - (sin^2 x / sin^2 x)
= 2 cot x/ (cot^2 x - 1)