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If 2 Cos^(2)B - 1 = Tan^(2) A then Cos A...

If `2 Cos^(2)B - 1 = Tan^(2) A` then `Cos A Cos B =`

A

`1/2`

B

`pm (1)/(sqrt(2))`

C

`(1)/(4)`

D

`pm 1/4`

Text Solution

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The correct Answer is:
B
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