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Ukrainian Mathematical Journal

, Volume 65, Issue 6, pp 938–944 | Cite as

On the Lebesgue Inequality on Classes of \( \bar{\psi} \) -Differentiable Functions

  • N. M. Zaderei
  • P. V. Zaderei
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We consider the deviations of Fourier sums in the spaces \( {C^{\bar{\psi}}} \). The estimates of these deviations are expressed via the best approximations of the \( \bar{\psi} \) -derivatives of functions in the Stepanets sense. The sequences \( \bar{\psi} \) = (ψ1, ψ2) are quasiconvex.

Keywords

Fourier Series Periodic Function Naukova Dumka English Translation Differentiable Function 
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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • N. M. Zaderei
    • 1
  • P. V. Zaderei
    • 2
  1. 1.“Kyiv Polytechnic Institute” Ukrainian National Technical UniversityKyivUkraine
  2. 2.Kyiv National University of Technologies and DesignKyivUkraine

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