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KöMaL problem A, 2018

Geometry Difficulty 7.0 National Olympiad, round 2 Prove it Hungary

Circle ω\omega lies in the interior of circle Ω\Omega, on which a point XX moves. The tangents from XX to ω\omega intersect Ω\Omega for the second time at points A≠XA\ne X and B≠XB\ne X. Prove that the lines ABAB are either all tangent to a fixed circle, or they all pass through a point.

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