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OM tangent to circle wanted - All-Russian MO 2001 Regional (R4) 9.7

Source:

September 26, 2024
geometrytangent

Problem Statement

A circle inscribed in an angle with vertex OO touches its sides at points AA and BB, KK is an arbitrary point on the smaller of the two arcs ABAB of this circle. On the line OBOB a point LL is taken such that the lines OAOA and KLKL are parallel. Let MM be the intersection point of the circle ω\omega circumscribed around triangle KLBKLB, with line AKAK, with MM different from KK. Prove that line OMOM touches circle ω\omega.