MathDB
3 Circles

Source: NZMO 2

October 6, 2021
geometry

Problem Statement

Let ABAB be a chord of circle Γ\Gamma. Let OO be the centre of a circle which is tangent to ABAB at CC and internally tangent to Γ\Gamma at PP. Point CC lies between AA and BB. Let the circumcircle of triangle POCPOC intersect Γ\Gamma at distinct points PP and QQ. Prove that AQP=CQB\angle{AQP}=\angle{CQB}.