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Ukrainian Mathematical Journal

, Volume 59, Issue 8, pp 1192–1211 | Cite as

Multiple Fourier sums and ϕ-strong means of their deviations on the classes of \(\bar \psi \)-differentiable functions of many variables

  • A. I. Stepanets
  • R. A. Lasuriya
Article

Abstract

We present the results concerning the approximation of \(\bar \psi \)-differentiable functions of many variables by rectangular Fourier sums in uniform and integral metrics and establish estimates for the ϕ-strong means of their deviations in terms of the best approximations.

Keywords

Fourier Series Orthogonal Projection Differentiable Function Approximation Theory Trigonometric Series 
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Copyright information

© Springer Science+Business Media, Inc. 2007

Authors and Affiliations

  • A. I. Stepanets
  • R. A. Lasuriya
    • 1
  1. 1.Abkhazia UniversitySukhumi

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