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KöMaL problem A, 2023

Geometry Difficulty 6.0 National Olympiad Prove it Hungary

Let ABCABC be a triangle and OO be its circumcenter. Let DD, EE and FF be the respective tangent points of the incircle of △ABC\triangle ABC, and sides BCBC, CACA and ABAB. Let MM and NN be the respective midpoints of sides ABAB and ACAC. Let M′M' and N′N' be the respective reflections of points MM and NN across lines DEDE and DFDF. Let lines CM′CM' and BN′BN' intersect lines DEDE and DFDF at points HH and JJ, respectively.

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