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

Select ALL that apply.

$\cos^{2}{\theta} - \sin^{2}{\theta}$

$2\cos^{2}{\theta} - 1$

$2\cos^{2}{\theta} + 1$

$1 - 2\sin^{2}{\theta}$