If A+B+C =pi and cos A = cos B cos C the...

If `A+B+C =pi and cos A = cos B cos C` then `cot B. cot C =`............. A) `1/3` B) `1` C) `2` D) `1/2`

A

`1/3`

B

1

C

2

D

`1/2`

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The correct Answer is:

D

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