On the best $$$L_2$$$-approximations of multivariable functions by means of splines

V.F. Babenko (Dnipropetrovsk National University, Institute of Applied Mathematics and Mechanics of NAS of Ukraine), https://orcid.org/0000-0001-6677-1914
G.S. Zhiganova (Dnipropetrovsk National University)


We obtain sharp inequalities of Jackson type for the best approximations of functions in $$$L_2(\mathbb{R}^m)$$$ by means of partial sums of wavelet series in case of multidimensional analogues of Shannon-Kotelnikov wavelets.


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DOI: https://doi.org/10.15421/240701



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ISSN (Online): 2664-5009
ISSN (Print): 2664-4991