One-sided approximation by entire functions
نویسندگان
چکیده
منابع مشابه
One-sided approximation by entire functions
Let f : R→ R have an nth derivative of finite variation Vf(n) and a locally absolutely continuous (n− 1)st derivative. Denote by E±(f, δ)p the error of onesided approximation of f (from above and below, respectively) by entire functions of exponential type δ > 0 in Lp(R)–norm. For 1 ≤ p ≤ ∞ we show the estimate E±(f, δ)p ≤ C n π1/pVf(n)δ −n− 1 p , with constants Cn > 0.
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ژورنال
عنوان ژورنال: Journal of Approximation Theory
سال: 2006
ISSN: 0021-9045
DOI: 10.1016/j.jat.2005.12.003