A sequence of extremal problems for trigonometric polynomials
نویسندگان
چکیده
منابع مشابه
A note on some extremal problems for trigonometric polynomials
We consider the problem of finding the trigonometric polynomial θ0 + m ∑ j=1 θ2j−1 sin(jx) + θ2j cos(jx) with minimal sup-norm on the interval [−π, π], where one coefficient in the polynomial, say θk (0 ≤ k ≤ 2m), has been fixed. A complete solution of this problem is given, which depends sensitively on the ratio k/m, and the problem of uniqueness is discussed. Several examples are presented to...
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ژورنال
عنوان ژورنال: Journal of Mathematical Analysis and Applications
سال: 1988
ISSN: 0022-247X
DOI: 10.1016/0022-247x(88)90330-7