FAR EASTERN BRANCH OF THE RUSSIAN ACADEMY OF SCIENCES
INSTITUTE OF APPLIED MATHEMATICS KHABAROVSK DIVISION
Far Eastern Mathematical Journal
On the value of the widths of some classes of functions from L_2 |
Langarshoev M.R. |
2021, issue 1, P. 61-70 DOI: https://doi.org/10.47910/FEMJ202106 |
Abstract |
| In this paper we find sharp inequalities of Jackson-Stechkin type between the best approximations of periodic differentiable functions by trigonometric polynomials and generalized moduli of continuity of m-th order in the space L_2. The exact values of various n-widths of classes of functions from L_2 defined by the generalized modus of continuity of the $r$-th derivative of the function f are calculated. |
Keywords: best approximation, trigonometric polynomials, generalized modulus of continuity of higher order, n-widths |
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References |
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