If O is the in-centre of ∆ABC; if ∠BOC = 120°,

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If O is the in-centre of ∆ABC; if ∠BOC = 120°, then the measure of ∠BAC is

1. 30°
2. 60°
3. 150°
4. 75°

Correct Option: B

On the basis of given in question , we draw a figure triangle ABC ,

BO, CO and AO are internal bisectors of ∠B, ∠C and ∠A respectively.
Here , ∠BOC = 120°

∴ ∠BOC = 90° +	∠A
	2

⇒ 120° = 90° +	∠A
	2

⇒	∠A	= 120° - 90° = 30°
	2

∴ ∠A = 30 × 2 = 60°