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Which of the following equations represents the double-angle formula for the $\tan{2\theta}$?

Select ALL that apply.

$\cfrac{\tan{\theta}}{1 - \tan^{2}{\theta}}$

$\cfrac{2 \tan{\theta}}{1 + \tan^{2}{\theta}}$

$\cfrac{2 \tan{\theta}}{1 - \tan{\theta}}$

$\cfrac{2 \tan{\theta}}{1 - \tan^{2}{\theta}}$