On the order of an approximation of functions on sets of positive measure by linear positive polynomial operators
Tóm tắt
It is proved that at almost all points the order of approximation, even of one of the functions 1, cos x,sin x by means of a sequence of linear positive polynomial operators having uniformly bounded norms, is not higher than 1/n2. Refinements of this result are given for operators of convolution type.
Tài liệu tham khảo
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