Best approximations of the classes $B_{p,\,\theta}^{r}$ of periodic functions of many variables in uniform metric

• Datum: 2006
• Hauptverfasser: Romanyuk, A. S., Романюк, А. С.
• Format: Artikel
• Sprache: Russisch; Englisch
• Veröffentlicht: Institute of Mathematics, NAS of Ukraine 2006
• Online Zugang: https://umj.imath.kiev.ua/index.php/umj/article/view/3541
• Назва журналу: Ukrains’kyi Matematychnyi Zhurnal

We obtain estimates exact in order for the best approximations of the classes $B_{\infty,\,\theta}^{r}$ of periodic functions of two variables in the metric of $L_{\infty}$ by trigonometric polynomials whose spectrum belongs to a hyperbolic cross. We also investigate the best approximations of the c...