Let be an obtuse triangle, and let denote its orthocenter. Let denote the circle with center and radius . Let and be defined in a similar way. For all points in the plane of triangle let circle be defined in the following way (if possible): take the polars of point with respect to circles , and , and let be the circumcircle of the triangle defined by these three lines.
With a possible exception of finitely many points find the locus of points for which point lies on circle .
, 2024
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