Cite this article as:
Lukashov А. L., Tyshkevich S. . Extremal Rational Functions on Several Arcs of the Unit Circle with Zeros on these Arcs. Izv. Saratov Univ. (N. S.), Ser. Math. Mech. Inform., 2009, vol. 9, iss. 1, pp. 8-13. DOI: https://doi.org/10.18500/1816-9791-2009-9-1-8-13
Extremal Rational Functions on Several Arcs of the Unit Circle with Zeros on these Arcs
The solution of anextrema lproblem aboutrational function with fixed denominator and leading coefficient of nominator which is deviatedleast from zero on several arcs of the unit circle is given under restrictions on the location of zeros and additional conditions on mutual position of the arcs and zeros of denominator. The extremal function is represented in terms of the density of harmonic measure.
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