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International Mathematical Olympiad 2024 — Official contest Question 4

IMO · International Mathematical Olympiad 2024 — Official contest

Question 4

Let $ABC$ be a triangle with $AB\lt AC\lt BC$. Let the incentre and incircle of triangle $ABC$ be $I$ and $\omega$, respectively. Let $X$ be the point on line $BC$ different from $C$ such that the line through $X$ parallel to $AC$ is tangent to $\omega$. Similarly, let $Y$ be the point on line $BC$ different from $B$ such that the line through $Y$ parallel to $AB$ is tangent to $\omega$. Let $AI$ intersect the circumcircle of triangle $ABC$ again at $P\ne A$. Let $K$ and $L$ be the midpoints of $AC$ and $AB$, respectively.
Prove that $\angle KIL+\angle YPX=180^\circ$.