MathDB
Tangent circles

Source: Russian TST 2018, Day 9 P2 (Group NG), P4 (Groups A & B)

March 30, 2023
geometrytangency

Problem Statement

The point KK{} is the middle of the arc BACBAC of the circumcircle of the triangle ABCABC. The point II{} is the center of its inscribed circle ω\omega. The line KIKI intersects the circumcircle of the triangle ABCABC at TT{} for the second time. Prove that the circle passing through the midpoints of the segments BC,BTBC, BT and CTCT is tangent to the circle which is symmetric to ω\omega with respect to BCBC.