Abstract
We establish for 0<p<1 the analog of the Bernstein- Zygmund inequality for the derivative of a trigonometric polynomial We prove weighted inequalities, exact in the sense of order, for trigonometric polynomials and their derivatives in various integral metrics with exponents 0<p, q≤∞.
Similar content being viewed by others
Literature cited
S. M. Nikol'skii, The Approximation of Functions of Several Variables and Embedding Theorems [in Russian], Izdat. Nauka, Moscow (1969).
D. Jackson, “Certain problems of closest approximation,” Bull. Amer. Math. Soc.,39, 889–906 (1933).
N. K. Bari, “A generalization of the inequalities of S. N. Bernstein and A. A. Markov,” Izv. Akad. Nauk SSSR, Ser. Matem.,18, 59–76 (1954).
M. K. Potapov, “Certain inequalities for polynomials and their derivatives,” Vestnik Moskov. Gos. Univ., Ser. Matem. i Mekhan., No. 2, 10–19 (1960).
Yu. A. Brudnyi, “Approximation by entire functions on the exterior of a segment and a half-line,” Dokl. Akad. Nauk SSSR,124, No. 4, 739–742 (1959).
G. Szego, Orthogonal Polynomials, American Mathematical Society (1974).
Author information
Authors and Affiliations
Additional information
Translated from Matematicheskie Zametki, Vol. 18, No. 4, pp. 489–498, October, 1975.
In conclusion, the author thanks S. B. Stechkin for his help in this work.
Rights and permissions
About this article
Cite this article
Iva, V.I. Certain inequalities in various metrics for trigonometric polynomials and their derivatives. Mathematical Notes of the Academy of Sciences of the USSR 18, 880–885 (1975). https://doi.org/10.1007/BF01153038
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF01153038