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Iran geometry

Source: Iranian TST 2020, second exam day 1, problem 3

March 11, 2020
geometrycircumcircleincenterIranian TST

Problem Statement

Given a triangle ABCABC with circumcircle Γ\Gamma. Points EE and FF are the foot of angle bisectors of BB and CC, II is incenter and KK is the intersection of AIAI and EFEF. Suppose that TT be the midpoint of arc BACBAC. Circle Γ\Gamma intersects the AA-median and circumcircle of AEFAEF for the second time at XX and SS. Let SS' be the reflection of SS across AIAI and JJ be the second intersection of circumcircle of ASKAS'K and AXAX. Prove that quadrilateral TJIXTJIX is cyclic.
Proposed by Alireza Dadgarnia and Amir Parsa Hosseini