Question

How to prove that angle BAC is equal to 90 degrees + half angle A

Answer 1

Answer:

∠1=∠2,∠4=∠5

In ΔABC

∠A+∠B+∠C=180

∠A+2∠2+2∠5=180

∠2+∠5=90− 1/2

∠A

Now in ΔBOC

∠2+∠5+∠BOC=180

90− 1/2

∠A+BOC=180

∠BOC=90+ 1/2

∠A

∠BOC=90+ 1/2