Approximation of classes $\overline{\psi}$-differentiated functions by the Fourier sums

• Date: 2015
• Main Authors: Bodra, V. I., Zaderey, P. V., Бодра, В. І., Задерей, П. В.
• Format: Article
• Language: Ukrainian
• Published: Інститут математики НАН України 2015
• Online Access: https://trim.imath.kiev.ua/index.php/trim/article/view/280
• Journal Title: Transactions of Institute of Mathematics of NAS of Ukraine

We consider deviations of Fourier sums on the spaces $C^{\overline{\psi}}_{\infty}$ and estimates of these deviations are expressed by the best approximation $\overline{\psi}$-derivative functions of two variables in the understanding of A.I.Stepanets are obtained. The sequence $\psi_i^{(j)}(k_i),$...