In ∆ABC, the bisectors of ∠B and ∠C intersect each other at a point O

[Veerendra]

In ∆ABC, the bisectors of ∠B and ∠C intersect each other at a point O. Prove that
∠BOC = 90°+ 1/2 ∠A.

[Veerendra]

Given In ∆ABC, OS and OC are the angle bisectors of∠ABC and ∠ACB, respectively.