On the region of values of the system $\{f(z_1),\dots,f(z_n)\}$ in the class of typically real functions. II
Zapiski Nauchnykh Seminarov POMI, Computational methods and algorithms. Part XVIII, Tome 323 (2005), pp. 24-33
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The paper studies the region $D_{m,1}(T)$ of values of the system $\{f(z_1),f(z_2),\dots,f(z_m),f(r)\}$, $m\ge1$, where $z_j$ ($j=1,2,\dots,m$) are arbitrary fixed points of the disk $U=\{z:|z|<1\}$ with $\operatorname{Im}z_j\ne0$ ($j=1,2,\ldots,m$), and $r$, $0, is fixed, on the class $T$ of functions $f(z)=z+a_2z^2+\cdots$ regular in the disk $U$ and satisfying in the latter the condition $\operatorname{Im}f(z)\operatorname{Im}z>0$ for $\operatorname{Im}z\ne0$. An algebraic characterization of the set $D_{m,1}(T)$ in terms of nonnegative Hermitian forms is given, and all the boundary functions are described. As an implication, the region of values of $f(z_m)$ in the subclass of functions from the class $T$ with prescribed values $f(z_k)$ ($k=1,2,\dots,m-1$) and $f(r)$ is determined.
@article{ZNSL_2005_323_a2,
author = {E. G. Goluzina},
title = {On the region of values of the system $\{f(z_1),\dots,f(z_n)\}$ in the class of typically real {functions.~II}},
journal = {Zapiski Nauchnykh Seminarov POMI},
pages = {24--33},
year = {2005},
volume = {323},
language = {ru},
url = {http://geodesic.mathdoc.fr/item/ZNSL_2005_323_a2/}
}
TY - JOUR
AU - E. G. Goluzina
TI - On the region of values of the system $\{f(z_1),\dots,f(z_n)\}$ in the class of typically real functions. II
JO - Zapiski Nauchnykh Seminarov POMI
PY - 2005
SP - 24
EP - 33
VL - 323
UR - http://geodesic.mathdoc.fr/item/ZNSL_2005_323_a2/
LA - ru
ID - ZNSL_2005_323_a2
ER -
E. G. Goluzina. On the region of values of the system $\{f(z_1),\dots,f(z_n)\}$ in the class of typically real functions. II. Zapiski Nauchnykh Seminarov POMI, Computational methods and algorithms. Part XVIII, Tome 323 (2005), pp. 24-33. http://geodesic.mathdoc.fr/item/ZNSL_2005_323_a2/
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