Abstract:
Inequalities for the derivatives with respect to φ=argz the functions ReP(z), |P(z)|2 and argP(z) are established for an algebraic polynomial P(z) at points on the circle |z|=1. These estimates depend, in particular, on the constant term and the leading coefficient of the polynomial P(z) and improve the classical Bernstein and Turan inequalities. The method of proof is based on the techniques of generalized reduced moduli.
\Bibitem{Dub00}
\by V.~N.~Dubinin
\paper Distortion theorems for polynomials on a~circle
\jour Sb. Math.
\yr 2000
\vol 191
\issue 12
\pages 1797--1807
\mathnet{http://mi.mathnet.ru/eng/sm528}
\crossref{https://doi.org/10.1070/sm2000v191n12ABEH000528}
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This publication is cited in the following 20 articles:
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V. N. Dubinin, “Conformal mappings and inequalities for algebraic polynomials. II”, J. Math. Sci. (N. Y.), 129:3 (2005), 3823–3834