Direct and inverse approximation theorems in the Besicovitch – Musielak – Orlicz spaces of almost periodic functions
DOI:
https://doi.org/10.37863/umzh.v74i5.7045Ключові слова:
пряма апроксимаційна теорема, обернена апроксимаційна теорема, нерівність типу Джексона, узагальнений модуль гладкості.Анотація
УДК 517.5
Прямі та обернені теореми наближення в просторах Безиковича-Мусєлака-Орлича майже періодичних функцій
У термiнах найкращих наближень функцiй та узагальнених модулiв гладкостi доведено прямi та оберненi апроксимацiйнi теореми для майже перiодичних за Безиковичем функцiй, послiдовностi коефiцiєнтiв Фур’є яких мають єдину граничну точку в нескiнченностi, а їхнi норми Орлича є скiнченними. Особливу увагу придiлено вивченню випадкiв, коли сталi у цих теоремах непокращуванi.
Посилання
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