ISL 2010 G4
Let be the incenter of a triangle and be its circumcircle. Let the line intersect at a point . Let and be points on side and respectively such that . Finally, let be the midpoint of the segment . Prove that the lines and intersect on . (Hong Kong)
Official text Transcription from NuminaMath olympiads, checked word for word against the official paper. Quoted with source.
Official text: IMO 2010 Shortlist booklet, page 53.
Solutions
Official solution Solution 1 by the IMO Problem Selection Committee
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