On Jackson-Type Inequalities for Functions Defined on a Sphere

• Date: 2005
• Main Authors: Babenko, V. F., Doronin, V. G., Ligun, A. A., Shumeiko, A. A., Бабенко, В. Ф., Доронин, В. Г., Лигун, А. А., Шумейко, А. А.
• Format: Article
• Language: Russian; English
• Published: Institute of Mathematics, NAS of Ukraine 2005
• Online Access: https://umj.imath.kiev.ua/index.php/umj/article/view/3598
• Journal Title: Ukrains’kyi Matematychnyi Zhurnal

We obtain exact estimates of the approximation in the metrics $C$ and $L_2$ of functions, that are defined on a sphere, by means of linear methods of summation of the Fourier series in spherical harmonics in the case where differential and difference properties of functions are defined in the space...