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SMO 2017 Open Round 2 Question 1

SMO · SMO 2017 Open Round 2

Question 1

The incircle of $\triangle ABC$ touches the sides $BC,CA,AB$, at $D,E,F$ respectively. A circle through $A$ and $B$ encloses $\triangle ABC$ and intersects the line $DE$ at $P$ and $Q$. Prove that the midpoint of $AB$ lies on the circumcircle of $\triangle PQF$.