ISL 2019 G6
Let be the incentre of acute-angled triangle . Let the incircle meet , and at , and , respectively. Let line intersect the circumcircle of the triangle at and , such that lies between and . Prove that . (Slovakia)
Official text Transcription from NuminaMath olympiads, checked word for word against the official paper. Quoted with source.
Official text: IMO 2019 Shortlist booklet, page 10.
Solutions
Official solution Solution 1 by the IMO Problem Selection Committee
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