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

Use the trig identity: $\left(1 + \cos 2 a\right) = 2 {\cos}^{2} a$.
$\tan x . \left(1 + \cos 2 x\right) =$(sin x/cos x)$. 2 {\cos}^{2} x$ =