Hahn’s pairs and zero inverse problem
Journal Title: Математичні Студії - Year 2017, Vol 48, Issue 1
Abstract
We prove that for a function α0:[0,1]→R there exists a separately continuous function f:[0,1]2→R such that E0(fx)=α0(x) on [0,1] if and only if α0 is the nonnegative lower semicontinuous function, where fx(y)=f(x,y) for any x,y,∈[0,1] and E0(g) is the best approximation of a function g by a constant.
Authors and Affiliations
Volodymyr Maslyuchenko, V. S. Mel’nyk, Halyna Voloshyn
Keywords
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- EP ID EP302718
- DOI 10.15330/ms.48.1.74-81
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Hahn’s pairs and zero inverse problem
We prove that for a function α0:[0,1]→R there exists a separately continuous function f:[0,1]2→R such that E0(fx)=α0(x) on [0,1] if and only if α0 is the nonnegative lower semicontinuous function, where fx(y)=f(x,y) for...
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