MathDB

8

Part of 1996 Korea National Olympiad

Problems(1)

Geometry!

Source: 1996 Korea National Olympiad #8

3/22/2018
Let △ABC\triangle ABC be the acute triangle such that AB≠AC.AB\ne AC. Let VV be the intersection of BCBC and angle bisector of ∠A.\angle A. Let DD be the foot of altitude from AA to BC.BC. Let E,FE,F be the intersection of circumcircle of △AVD\triangle AVD and CA,ABCA,AB respectively. Prove that the lines AD,BE,CFAD, BE,CF is concurrent.
geometryangle bisectorcircumcircle