On three disjoint domains |
L. V. Kovalev |
2000, issue 1, P. 3–7 |
Abstract |
The paper deals with the following problem, stated in [Zbl.830.30014] by V. N. Dubinin and earlier, in different form, by G. P. Bakhtina [Zbl.585.30027]. Let $a_0=0, |a_1|=\dots=|a_n|=1, a_k\in B_k\in\overline{\mathbb C}$, where $B_0,\dots,B_n$ are disjoint domains, and $B_1,\dots,B_n$ are symmetric about the unit circle. Find the exact upper bound for $\prod_{k=0}^n r(B_k,a_k)$, where $r(B_k,a_k)$ is the inner radius radius of $B_k$ with respect to $a_k$. For $n\ge3$ this problem was recently solved by the author. In the present paper, it is solved for $n=2$. |
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References |
[1] G. V. Kuz'mina, “Metody geometricheskoj teorii funkcij I, II”, Algebra i analiz, 9:3 (1997), 41–103; 5, 1–50. [2]A. Yu. Solynin, “Moduli i e'kstremal'no-metricheskie problemy”, Algebra i analiz, 11:1 (1999), 3–86. [3] V. N. Dubinin, “Simmetrizaciya v geometricheskoj teorii funkcij kompleksnogo peremennogo”, UMN, 49:1 (1994), 3–76. [4] G. P. Baxtina, “O konformnyx radiusax simmetrichnyx nenalegayushhix oblastej”, Sovremennye voprosy veshhestvennogo i kompleksnogo analiza, In-t matematiki AN USSR, Kiev, 1984, 21–27. [5] G. M. Goluzin, Geometricheskaya teoriya funkcij kompleksnogo peremennogo, 2-oe izd., In. lit., M., 1966. [6] S. Stoilov, Teoriya funkcij kompleksnogo peremennogo, t. 2, In. lit., M., 1962. [7] L. V. Kovalev, “O vnutrennix radiusax simmetrichnyx nenalegayushhix oblastej”, Izv. vuzov. Matematika, 2000, № 6, 80–81. [8] V. N. Dubinin, “Razdelyayushhee preobrazovanie oblastej i zadachi ob e'kstremal'nom razbienii”, Zap. nauchn. semin. LOMI, 168, 1988, 48–66. [9] V. N. Dubinin, “Metod simmetrizacii v zadachax o nenalegayushhix oblastyax”, Matem. sb., 128:1 (1985), 110–123. [10] E'. M. Galeev, V. M. Tixomirov, Kratkij kurs teorii e'kstremal'nyx zadach, Izd-vo Mosk. un-ta, M., 1989. [11] G. Polia, G. Sege, Izoperimetricheskie neravenstva v matematicheskoj fizike, Fizmatgiz, M., 1962. |