Simplify the following expression by using sum or difference identities. $$ \cos \left(\frac{\pi}{12}\right) \cos \left(-\frac{\pi}{12}\right)+\sin \left(\frac{\pi}{12}\right) \sin \left(-\frac{\pi}{12}\right) $$ This quest
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Step 1: The given expression is: $$ \cos \left(\frac{\pi}{12}\right) \cos \left(-\frac{\pi}{12}\right)+\sin \left(\frac{\pi}{12}\right) \sin \left(-\frac{\pi}{12}\right) $$ This expression resembles the cosine difference identity, which is: $$ \cos(A - B) = \cos A Show more…
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