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arXiv · 1005.5555

On the best approximation of certain classes of periodic functions by trigonometric polynomials

A. S. Serdyuk·Ie. Yu. Ovsii
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Abstract

We obtain the estimates for the best approximation in the uniform metric of the classes of $2π$-periodic functions whose $(ψ,β)$-derivatives have a given majorant $ω$ of the modulus of continuity. It is shown that the estimates obtained here are asymptotically exact under some natural conditions on the parameters $ψ,$ $ω$ and $β$ defining the classes

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A. S. Serdyuk, Ie. Yu. Ovsii. 2011-04-14. On the best approximation of certain classes of periodic functions by trigonometric polynomials. https://arxiv.org/abs/1005.5555

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