Criterion of the best non-symmetric approximant for multivariable functions in spaces $$$L_{p_1,...,p_n}$$$

V.M. Traktyns'ka (Oles Honchar Dnipropetrovsk National University)
M.Ye. Tkachenko (Oles Honchar Dnipropetrovsk National University)


The questions of the characterization of the best nonsymmetric approximant for the multivariable functions in spaces with mixed integral metric were considered in this article. The criterion of best nonsymmetric approximant in these spaces is obtained.


mixed integral metric; the best non-symmetric approximant; non-symmetric norm


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