The maximum modulus of a trigonometric trinomial
نویسندگان
چکیده
منابع مشابه
The maximum modulus of a trigonometric trinomial
Let Λ be a set of three integers and let CΛ be the space of 2π-periodic functions with spectrum in Λ endowed with the maximum modulus norm. We isolate the maximum modulus points x of trigonometric trinomials T ∈ CΛ and prove that x is unique unless |T | has an axis of symmetry. This permits to compute the exposed and the extreme points of the unit ball of CΛ, to describe how the maximum modulus...
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ژورنال
عنوان ژورنال: Journal d'Analyse Mathématique
سال: 2008
ISSN: 0021-7670,1565-8538
DOI: 10.1007/s11854-008-0028-2