If A+B+C=(3pi)/2, t h e ncos2A+cos2B+cos...

If `A+B+C=(3pi)/2, t h e ncos2A+cos2B+cos2C` is equal to `1-4cos Acos BcosC` `4sinAsinBsinC` `1+2cosAcosBcosC` `1-4sinAsinBsinC`

A

`1-4cosA cosBcosC`

B

`4sinAsinB sinC`

C

`1+2 cosAcosBcosC`

D

`1-4sinAsinBsinC`

Verified by Experts

The correct Answer is:

D

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