If cos^(-1)((x)/(3))+cos^(-1)((y)/(2))=(...

If `cos^(-1)((x)/(3))+cos^(-1)((y)/(2))=(theta)/(2)`, then the value of `4x^(2)-12xy cos((theta)/(2))+9y^(2)` is equal to :

A

`18(1+cos theta)`

B

`18(1-cos theta)`

C

`36(1+cos theta)`

D

`36(1-cos theta)`

Verified by Experts

The correct Answer is:

B

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