منابع مشابه
Sharp Jackson inequalities
For trigonometric polynomials on [− , ] ≡ T , the classical Jackson inequalityEn(f )p C r (f, 1/n)p was sharpened by M. Timan for 1<p<∞ to yield n−r { n ∑ k=1 ksr−1Ek(f )p }1/s C r (f, n−1)p where s =max(p, 2). In this paper a general result on the relations between systems or sequences of best approximation and appropriate measures of smoothness is given. Approximation by algebraic polynomials...
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ژورنال
عنوان ژورنال: Journal of Approximation Theory
سال: 2008
ISSN: 0021-9045
DOI: 10.1016/j.jat.2007.04.015