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cos A .cos (120^@ +A ) . Cos (120 ^@ -...

`cos A .cos (120^@ +A ) . Cos (120 ^@ -A )` is

A

0

B

`cos 3A `

C

`1/4 cos 3A `

D

`4/3 cos 3A `

Text Solution

Verified by Experts

The correct Answer is:
C
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