3 A is equal to : - Vidyadip

MCQ

$\cos 3 A$ is equal to :

A
$3 \cos A-4 \cos ^3 A$
B
$3 \cos A+4 \cos ^3 A$
✓
$4 \cos ^3 A-3 \cos A$
D
None of these

✓

Answer

Correct option: C.

$4 \cos ^3 A-3 \cos A$

(C )

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