Abstract
Asymptotic estimates, expressed in terms of the value of the modulus of continuity of r-th order (r≥2) at the point t=π/n of a functionfε C 2π or of the (ψ, β)-derivative of a functionf∈ C ψB C, are established for the deviations of continuous periodic functions from their Fourier sums.
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Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 42, No. 6, pp. 747–755, June, 1990.
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Gavrilyuk, V.T. Asymptotic estimates of approximation of continuous periodic functions by Fourier sums. Ukr Math J 42, 659–666 (1990). https://doi.org/10.1007/BF01058908
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DOI: https://doi.org/10.1007/BF01058908