MathDB
circumcircle tangent to angle bisector

Source: Sharygin 2010 Final 8.1

October 2, 2018
geometrycircumcircleangle bisectortangent

Problem Statement

For a nonisosceles triangle ABCABC, consider the altitude from vertex AA and two bisectrices from remaining vertices. Prove that the circumcircle of the triangle formed by these three lines touches the bisectrix from vertex AA.