The approximation by partial sums of Fourier series
نویسندگان
چکیده
منابع مشابه
The Approximation by Partial Sums of Fourier Series
uniformly in x as h—»0, we shall say briefly that/ belongs to Lip a. Following 4](1)) we shall say that/ belongs to a) uniformly as *—>0. a notation already used (see Zygmund lipa, 0<a<l, if \f(x+h)-f(x)\=o(\h It is a classical result of Lebesgue (see Zygmund [5, p. 61 ] ; hereafter this book will be denoted by T.S.) that if / belongs to Lip a and if sn denotes the nth partial sum of the Fourie...
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 1946
ISSN: 0002-9947
DOI: 10.1090/s0002-9947-1946-0015538-0