Sharp estimates for the maximum over minimum modulus of rational functions
نویسندگان
چکیده
منابع مشابه
Sharp Estimates for the Maximum over Minimum Modulus of Rational Functions
Let m, n ≥ 0, λ > 1, and R be a rational function with numerator, denominator of degree ≤ m,n, respectively. In several applications, one needs to know the size of the set S ⊂ [0, 1] such that for r ∈ S, max |z|=r |R (z)| / min |z|=r |R (z)| ≤ λ. In an earlier paper, we showed that meas (S) ≥ 1 4 exp ( − 13 log λ ) , where meas denotes linear Lebesgue measure. Here we obtain, for each λ, the sh...
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 2001
ISSN: 0002-9939,1088-6826
DOI: 10.1090/s0002-9939-01-06268-2