The value of cos left(frac{7 pi}{12}right) is | vedclass

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(C) We can write $\frac{7 \pi}{12}$ as $\frac{\pi}{3} + \frac{\pi}{4}$.Using the formula $\cos(A + B) = \cos A \cos B - \sin A \sin B$:$\cos \left(\fr

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$\frac{\sqrt{2}-\sqrt{6}}{4}$

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(C) We can write $\frac{7 \pi}{12}$ as $\frac{\pi}{3} + \frac{\pi}{4}$.Using the formula $\cos(A + B) = \cos A \cos B - \sin A \sin B$:$\cos \left(\frac{\pi}{3} + \frac{\pi}{4}\right) = \cos \frac{\pi}{3} \cos \frac{\pi}{4} - \sin \frac{\pi}{3} \sin \frac{\pi}{4}$$= \left(\frac{1}{2}\right) \left(\frac{1}{\sqrt{2}}\right) - \left(\frac{\sqrt{3}}{2}\right) \left(\frac{1}{\sqrt{2}}\right)$$= \frac{1}{2 \sqrt{2}} - \frac{\sqrt{3}}{2 \sqrt{2}}$$= \frac{1 - \sqrt{3}}{2 \sqrt{2}} = \frac{\sqrt{2} - \sqrt{6}}{4}$

The value of $\cos \left(\frac{7 \pi}{12}\right)$ is

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