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IMO 2020 — Complete Shortlist Question 24

IMO Shortlist · IMO 2020 — Complete Shortlist

Question 24

Let $\Gamma$ and $I$ be the circumcircle and the incenter of an acute-angled triangle $A B C$.

Two circles $\omega_{B}$ and $\omega_{C}$ passing through $B$ and $C$, respectively, are tangent at $I$. Let $\omega_{B}$ meet the shorter arc $A B$ of $\Gamma$ and segment $A B$ again at $P$ and $M$, respectively. Similarly, let $\omega_{C}$ meet the shorter arc $A C$ of $\Gamma$ and segment $A C$ again at $Q$ and $N$, respectively. The rays $P M$ and $Q N$ meet at $X$, and the tangents to $\omega_{B}$ and $\omega_{C}$ at $B$ and $C$, respectively, meet at $Y$.

Prove that the points $A, X$, and $Y$ are collinear.