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KöMaL problem A, 2024

Geometry Difficulty 9.0 IMO level Find the answer Hungary

Let ABCABC be an obtuse triangle, and let HH denote its orthocenter. Let ωA\omega_A denote the circle with center AA and radius AHAH. Let ωB\omega_B and ωC\omega_C be defined in a similar way. For all points XX in the plane of triangle ABCABC let circle Ω(X)\Omega(X) be defined in the following way (if possible): take the polars of point XX with respect to circles ωA\omega_A, ωB\omega_B and ωC\omega_C, and let Ω(X)\Omega(X) be the circumcircle of the triangle defined by these three lines.
With a possible exception of finitely many points find the locus of points XX for which point XX lies on circle Ω(X)\Omega(X).

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