ISL 2023 G5
Let be an acute-angled triangle with circumcircle and circumcentre . Points and lie on such that and . Let meet at , and meet at . Prove that the circumcircles of triangles and have an intersection on line . (Malaysia)
Official text Transcription from NuminaMath olympiads, checked word for word against the official paper. Quoted with source.
Official text: IMO 2023 Shortlist booklet, page 9.
Solutions
Official solution Solution 1 by the IMO Problem Selection Committee
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