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If I is the incentre of a DeltaABC such ...

If I is the incentre of a `DeltaABC` such that `angleA=60^(@)`, then AI =

A

r

B

`r/2`

C

2r

D

none of these

Text Solution

Verified by Experts

The correct Answer is:
C
We know that the distances of the incentre I of `Delta` ABC from its vertices are given by
`IA=rcosecA/2,IB=rcosecB/2,IC=rcosecC/2`
Here, `A=60^(@)`
`thereforeIA=rcosec30^(@)=2r`
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