upgrade of problem 7 for grade 8-9, 239MO 2004
Source: 239MO 2004, grade 10-11, problem 8
December 11, 2004
geometrycircumcircleparallelogramconicsparabolaratiogeometric transformation
Problem Statement
Given a triangle . A point is chosen on a side . Some circle passes through , touches the side and intersects the circumcircle of triangle in points and such that the segment bisects and intersects sides and in points and . Prove that the circumcircle of triangle passes through a fixed point different from .
proposed by Sergej Berlov