MathDB
P3 Bosnia and Herzegovina JBMO TST

Source: Bosnia and Herzegovina JBMO TST 2018

July 14, 2018
geometry

Problem Statement

Let Γ\Gamma be circumscribed circle of triangle ABCABC (ABAC)(AB \neq AC). Let OO be circumcenter of the triangle ABCABC. Let MM be a point where angle bisector of angle BACBAC intersects Γ\Gamma. Let DD (DM)(D \neq M) be a point where circumscribed circle of the triangle BOMBOM intersects line segment AMAM and let EE (EM)(E \neq M) be a point where circumscribed circle of triangle COMCOM intersects line segment AMAM. Prove that BD+CE=AMBD+CE=AM.