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In a triangle ABC , if 3a = b + c , then...

In a triangle ABC , if 3a = b + c , then cot `B/2` cot `C/2` =

A

1

B

2

C

3

D

4

Text Solution

Verified by Experts

We have,
`3a=b+crArr4a=a+b+crArr4a=2srArrs=2a`
`thereforecotB/2cotC/2=sqrt((s(s-b))/((s-a)(s-c)))sqrt((s(s-c))/((s-a)(s-b)))`
`rArrcotB/2cotC/2=s/(s-a)=(2a)/(2a-a)=2`
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