Question

If the bisector of B and C of a triangle ABC meet at a point O, then prove that ang.BOC=90•+1/2ang.A

Answer 1

As we know A+B+C = 180

so, B+C = 180- A

in triangle BOC ,

we have three angles , OBC,BOC,and OCB

OBC = (B/2)

OCB = (C/2)

LET BOC = x

so , x + (B/2) + (C/2) = 180

FROM Equation 1

= x+ 90 - (A/2) =180

=x = 90+(A/2)

h.p