Abstract:
Markov's inequality for the derivative of algebraic polynomials is considered on $C^2$-smooth Jordan arcs. The asymptotically best estimate is given for the $k$th derivative for all $k=1,2,\dots$ . The best constant is related to the behaviour around the endpoints of the arc of the normal derivative of the Green's function of the complementary domain. The result is deduced from the asymptotically sharp Bernstein inequality for the $k$th derivative at inner points of a Jordan arc, which is derived from a recent result of Kalmykov and Nagy on the Bernstein inequality on analytic arcs. In the course of the proof we shall also need to reduce the analyticity condition in this last result
to $C^2$-smoothness.
Bibliography: 21 titles.
Keywords:Markov inequality, Jordan arc, normal derivative of Green's function.