If $\cos A + \cos B + \cos C = 0$, then $\cos \,\,3A + \cos \,\,3B + \cos \,\,3C$ is equal to

$8\,\,{\cos ^3}A\,\,{\cos ^3}B\,\,{\cos ^3}C$

JEE MATHEMATICS MCQ: MULTIPLE AND SUBMULTIPLE ANGLES

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Analyzing +4 | -1

\cos A + \cos B + \cos C = 0

, then

\cos \,\,3A + \cos \,\,3B + \cos \,\,3C

is equal to

View answer and explanation

Correct option: B

12\,\,\cos A\,\,\cos B\,\,\cos C

Option B (

12\\,\cos A\\,\cos B\\,\cos C

) is the correct answer because it follows from trigonometric identities and the given condition

\cos A + \cos B + \cos C = 0

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