Question

Bisectors  of angles B and C of a triangle ABC intersect each other at the point O .

prove <BOC= 90°+1/2 <A

Answer 1

heya refer diagram also..___$$$
<A=x
<B=y
<C=z
so in triange OBC
<O+<B+<C=180
<O=180-(<B+<C)
=180-(y/2+z/2)
=180-{(y+z)/2
=180-{(180-x)/2}
=180-90+x/2
=90+x/2
=90+<A/2

Answer 2

Answer

Hence Proved

Step-by-step explanation:

<A=x

<B=y

<C=z

so in triange OBC

<O+<B+<C=180

<O=180-(<B+<C)

=180-(y/2+z/2)

=180-{(y+z)/2  

=180-{(180-x)/2}

=180-90+x/2

=90+x/2

=90+<A/2