Question

In ΔABC, the bisector of ∠A intersects BC in D. Prove that BD=BC*AB/AB+AC and DC=BC*AC/AC+AB

Answer 1

In the attachments I have answered this problem.

Concept:

Angle bisector theorem:

If the vertical angle of a triangle is bisected the bisector divides the base into two segments which have same the ratio as the order of other two sides.

See the attachment for detailed solution