The exact Jackson–Stechkin inequality in 𝐿2,𝜇𝛼
https://doi.org/10.22405/2226-8383-2023-24-3-139-161
Abstract
Several extremal problems on the best mean-square approximation of the functions 𝑓, on a semiaxis with a power-law weight are solved in the paper, which can be applied in solving various problems. Exact Jackson–Stechkin-type inequalities are obtained for some classes of functions in which the values of the best approximations are estimated from above in terms of 𝑘-th order Hankel moduli of smoothness.
About the Author
Tilektes Ereshovich Tileubayev
Eurasian L. N. Gumilyov National University
Kazakhstan
Kazakhstan
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Review
For citations:
Tileubayev T.E. The exact Jackson–Stechkin inequality in 𝐿2,𝜇𝛼. Chebyshevskii Sbornik. 2023;24(3):139-161. (In Russ.) https://doi.org/10.22405/2226-8383-2023-24-3-139-161
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