olymmath

ISL 2023 G6

Let ABCA B C be an acute-angled triangle with circumcircle ω\omega. A circle Γ\Gamma is internally tangent to ω\omega at AA and also tangent to BCB C at DD. Let ABA B and ACA C intersect Γ\Gamma at PP and QQ respectively. Let MM and NN be points on line BCB C such that BB is the midpoint of DMD M and CC is the midpoint of DND N. Lines MPM P and NQN Q meet at KK and intersect Γ\Gamma again at II and JJ respectively. The ray KAK A meets the circumcircle of triangle IJKI J K at X≠KX \neq K.  Prove that ∠BXP=∠CXQ. \text { Prove that } \angle B X P=\angle C X Q \text {. }

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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