Question
$\cos 6 \theta=$(a) $32 \cos ^{6} \theta+48 \cos ^{\prime} \theta-18 \cos ^{2} \theta-1$(b) $32 \cos ^{6} \theta-48 \cos ^{4} \theta+18 \cos ^{2} \theta-1$(c) $32 \cos ^{6} \theta+48 \cos ^{4} \theta+8 \cos ^{2} \theta-1$(d) None of the above
Step 1
Here, we have $n=6$, so we get: \[(\cos \theta + i \sin \theta)^6 = \cos 6\theta + i \sin 6\theta\] Show more…
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