MathDB
Angle bisectors all the way through...

Source:

October 21, 2010
geometryrectanglegeometric transformationreflectioncircumcircleangle bisectorgeometry unsolved

Problem Statement

A point PP lies on the internal angle bisector of BAC\angle BAC of a triangle ABC\triangle ABC. Point DD is the midpoint of BCBC and PDPD meets the external angle bisector of BAC\angle BAC at point EE. If FF is the point such that PAEFPAEF is a rectangle then prove that PFPF bisects BFC\angle BFC internally or externally.