TY - JOUR
AU - S. B. Vakarchuk
AU - M. B. Vakarchuk
PY - 2022/08/09
Y2 - 2023/03/24
TI - $K$-functionals and extreme problems of the theory of approximation of the classes of analytic functions in a circle. II
JF - Ukrainsâ€™kyi Matematychnyi Zhurnal
JA - Ukr. Mat. Zhurn.
VL - 74
IS - 7
SE - Research articles
DO - 10.37863/umzh.v74i7.6981
UR - https://umj.imath.kiev.ua/index.php/umj/article/view/6981
AB - UDC 517.5The exact values of the Kolmogorov, Bernstein, and trigonometric $n$-widths of the classes defined by using the Hadamard compositions, generalized $K$-functionals, and majorants are obtained in the Hardy, Bergman, and Gvaradze Banach spaces. The exact values of the upper boundaries of the moduli of Fourier coefficients were also found in the indicated classes of functions.
ER -