An isosceles trapezoid ABCD (AB=CD) is given. A point P on its circumcircle is such that segments CP and AD meet at point Q. Let L be tha midpoint ofQD. Prove that the diagonal of the trapezoid is not greater than the sum of distances from the midpoints of the lateral sides to ana arbitrary point of line PL. inequalitiesgeometrygeometric inequalityisoscelestrapezoid