Problem

Source: Sharygin Finals 2023 9.1

Tags: Sharygin Geometry Olympiad, Sharygin 2023, median, Concyclic, geometry



The ratio of the median $AM$ of a triangle $ABC$ to the side $BC$ equals $\sqrt{3}:2$. The points on the sides of $ABC$ dividing these side into $3$ equal parts are marked. Prove that some $4$ of these $6$ points are concyclic.