Q2Long answerExercise 6.3
2 2 2 i.e., ∠A + ∠OBC + ∠OCB = 90° (Since BO and CO are bisectors of ∠B and ∠C) (1) But ∠BOC + ∠OBC + ∠OCB =180° (Angle sum property) (2) Subtracting (1) from (2), we have ∠BOC + ∠OBC + ∠OCB – ∠A – ∠OBC – ∠OCB = 180° – 90° i.e., ∠BOC = 90° + ∠A