MathDB
A computational geometry, midpoint of a side

Source: Iran TST 2007, Day 1

May 7, 2007
geometrytrigonometrycircumcircleangle bisectorgeometry proposed

Problem Statement

In triangle ABCABC, MM is midpoint of ACAC, and DD is a point on BCBC such that DB=DMDB=DM. We know that 2BC2AC2=AB.AC2BC^{2}-AC^{2}=AB.AC. Prove that BD.DC=AC2.AB2(AB+AC)BD.DC=\frac{AC^{2}.AB}{2(AB+AC)}