JEE MATHEMATICS MCQ: MULTIPLE AND SUBMULTIPLE ANGLES

1 Easy

1 of 1

Application +4 | -1

The value of the series

\cos \,\,12^\circ + \cos \,\,84^\circ + \cos \,\,132^\circ + \cos \,\,156^\circ

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Correct option: D

- \frac{1}{2}

Option D is correct because the sum of the cosine series simplifies to -1/2 using trigonometric identities.

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