Abstract
Let X and Y be linear normed spaces, W a set in X, A an operator from W into Y, and\(\mathfrak{W}\) the set
of all operators or the set ℒ of linear operators from X into Y. With δ>0 we put
.
We discuss the connection of\(v\left( {\delta , \mathfrak{M}} \right)\) with the Stechkin problem on best approximation of the operator A in W by linear bounded operators. Estimates are obtained for\(v\left( {\delta , \mathfrak{M}} \right)\) e.g., we write the inequality
, where H(Y) is Jung's constant of the space Y, and Ω(t) is the modulus of continuity of A in W.
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Translated from Matematicheskie Zametki, Vol. 22, No. 2, pp. 231–244, August, 1977.
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Arestov, V.V. Uniform regularization of the problem of calculating the values of an operator. Mathematical Notes of the Academy of Sciences of the USSR 22, 618–626 (1977). https://doi.org/10.1007/BF01780971
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DOI: https://doi.org/10.1007/BF01780971