AD = AO wanted, 2 circles and angle bisector related
Source: Switzerland - Swiss ΜΟ 2017 p1
July 14, 2020
geometryangle bisectorcirclesequal segments
Problem Statement
Let and be points on the circle with center , so that . Let be the intersection of the bisectors of and , different from . Let be the intersection of the straight line with the circumcircle of the triangle , different from . Show that .