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If A - B = (pi)/(3), then find cos A cos...

If A - B = `(pi)/(3)`, then find cos A cos B + sin A sin B.

A

`(1)/(2)`

B

`(1)/(3)`

C

2

D

1

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The correct Answer is:
A
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ARIHANT PUBLICATION BIHAR-TRIGONOMETRIC IDENTITIES-EXAM BOOSTER (FOR CRACKING EXAM)
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