circumcenter construction, ruler only, given circumcircle, incenter
Source: XII All-Ukrainian Tournament of Young Mathematicians, Qualifying p2
May 27, 2021
geometryconstructionRulerincenterUkrainian TYM
Problem Statement
The figure shows a triangle, a circle circumscribed around it and the center of its inscribed circle. Using only one ruler (one-sided, without divisions), construct the center of the circumscribed circle.