Best and partial best L1 approximations by polynomials to certain rational functions
نویسندگان
چکیده
منابع مشابه
Best Approximations by Smooth Functions
THEOREM 1.1 (U. Sattes). Let r > 2 and g E C[O, l]\B$,‘. Then f”EB$’ is a best approximation to g, in L” (such a best approximation necessari/J) exisrs) if and only if there exists a subinterual (a, /?) c IO. 1 I and a positilse integer M > r + 1 for which the following conditions hold (i) f”l,n.ll, is a Perfect spline of degree r with exactly) M ~ r -1 knots arzd I.f”““(s)l = I a. e. on [u,pI....
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ژورنال
عنوان ژورنال: Journal of Approximation Theory
سال: 1975
ISSN: 0021-9045
DOI: 10.1016/0021-9045(75)90113-6