Question

How do you verify the identity: `sin2x=(tanx)(1+cos2x)`?

Answer 1

Use the trig identity: `(1 + cos 2a) = 2 cos^2 a`.

`tan x.(1 + cos 2x) =`(sin x/cos x)`. 2cos^2 x` =
= 2.sin x . cos x = sin 2x#.