MathDB
Vietnam NMO 2002_2

Source:

October 26, 2008
geometrygeometric transformationreflectiongeometry proposed

Problem Statement

An isosceles triangle ABC ABC with AB \equal{} AC is given on the plane. A variable circle (O) (O) with center O O on the line BC BC passes through A A and does not touch either of the lines AB AB and AC AC. Let M M and N N be the second points of intersection of (O) (O) with lines AB AB and AC AC, respectively. Find the locus of the orthocenter of triangle AMN AMN.