Advanced Geometric Problem & Solution (Twice a week update) Now 4820 problems posted.
<Tri-2023-2046>, hint
Lei O' be the circumcenter of triangle ABC, and M be the midpoint of arc BC.
Since O lies on AM and OM//OP, and O',O,Q are colinear
<MO'Q=<POO'=<OPQ+<OQP, <OPQ=<OQP.
<MO'Q=2MAQ. Hence A,Q,O,P are concyclic, <PQO=<PAO=<QAO.
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