MathDB
2016 JBMO Shortlist G4

Source: 2016 JBMO Shortlist G4

October 8, 2017
geometryJBMO

Problem Statement

Let ABC{ABC} be an acute angled triangle whose shortest side is BC{BC}. Consider a variable point P{P} on the side BC{BC}, and let D{D} and E{E} be points on AB{AB} and AC{AC}, respectively, such that BD=BP{BD=BP} and CP=CE{CP=CE}. Prove that, as P{P} traces BC{BC}, the circumcircle of the triangle ADE{ADE} passes through a fixed point.