The best approximation of certain unbounded operators on classes of multivariable functions

V.F. Babenko; D.A. Levchenko

doi:10.15421/241205

The best approximation of certain unbounded operators on classes of multivariable functions

V.F. Babenko (Oles Honchar Dnipropetrovsk National University), https://orcid.org/0000-0001-6677-1914
D.A. Levchenko (Oles Honchar Dnipropetrovsk National University)

Abstract

We obtain the value of the best approximation of the linear combination, with non-negative coefficients, of the second partial derivatives and mixed derivatives of the second order on the class of multivariable functions with bounded third partial derivatives.

Keywords

best approximation of operator; module of continuity of operator; operator renewal; Kolmogorov type inequality

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References

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