One-sided approximation by entire functions
نویسنده
چکیده
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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ورودعنوان ژورنال:
- Journal of Approximation Theory
دوره 141 شماره
صفحات -
تاریخ انتشار 2006