\[1 - 2\sin^{2}\left( \frac{\pi}{4} + \theta \right) =] | MATH - FUNDAMENTAL TRIGONOMETRICAL | SolveeIt

$1 - 2\sin^{2}\left( \frac{\pi}{4} + \theta \right) =$

$\cos 2\theta$

$- \cos 2\theta$

$\sin 2\theta$

$- \sin 2\theta$

Answer

$- \sin 2\theta$

Explanation

$1 - 2\sin^{2}\left( \frac{\pi}{4} + \theta \right) = \cos\left( \frac{\pi}{2} + 2\theta \right) = - \sin 2\theta$ .

Question: \[1 - 2\sin^{2}\left( \frac{\pi}{4} + \theta \right) =\]...