R. B. Gardner, N. K. Govil and G. V. Milovanović, Bernstein-type inequalities for polar derivatives of polynomials, Extremal Problems and Inequalities of Markov-Bernstein Type for Algebraic ...
Two near minimax norms for polynomial approximation are presented. They are designed for approximation of both a function and its first derivative uniformly by polynomials over a given finite interval ...