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ITOT 41 Autumn 2019 - Junior O - Practice (sum 22; official best three 14) Question 2

ITOT · ITOT 41 Autumn 2019 - Junior O - Practice (sum 22; official best three 14)

Question 2

Let $\omega$ be a circle with centre $O$ and distinct points $A,C$ on it. For any point $P$ on $\omega$ distinct from $A,C$, let $X,Y$ be the midpoints of $AP,CP$. Let $H$ be the orthocentre of triangle $OXY$. Prove that the position of $H$ does not depend on the choice of $P$.