In acute triangle △ABC, O is its circumcenter, and points D,E lie on sides AB,AC (excluding endpoints) such that BC,DE are not parallel. Line BC meet DE at F, and the perpendicular bisectors of BD,CE meet at K. KO meets BC at L and AO meets DE at M. Prove that F,M,L,O are concyclic. geometryperpendicular bisectorcircumcircleHi