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Exact Jackson–Stechkin-type inequalities for 2π-periodic functions in L 2 and widths of some classes of functions

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Ukrainian Mathematical Journal Aims and scope

We consider the problem of finding exact inequalities for the best approximations of periodic differentiable functions by trigonometric polynomials and the m-order moduli of continuity in the space L 2 and present their applications. For some classes of functions defined by the indicated moduli of continuity, we calculate the exact values of n-widths in the space L 2.

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Authors and Affiliations

  1. Institute of Mathematics, Academy of Sciences of Tajikistan, Dushanbe, Tajikistan

    M. Sh. Shabozov

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  1. M. Sh. Shabozov
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Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 63, No. 10, pp. 1434–1440, October, 2011.

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Shabozov, M.S. Exact Jackson–Stechkin-type inequalities for 2π-periodic functions in L 2 and widths of some classes of functions. Ukr Math J 63, 1633–1639 (2012). https://doi.org/10.1007/s11253-012-0603-7

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  • DOI: https://doi.org/10.1007/s11253-012-0603-7

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