right angle wanted - 2005 Cuba MO 2.5
Source:
September 15, 2024
geometryright angleperpendicular
Problem Statement
On the circumcircle of triangle , point is taken in such a way that the perpendicular drawn by the point to the line cuts the circle also at the point , the perpendicular drawn by the point to the line cuts the circle also at point R and the perpendicular drawn by point to the line BC cuts the circle also at the point . Let be the center of this circle. Prove that .