An extremal problem for functions with positive real part

Author:
R. S. Gupta

Journal:
Proc. Amer. Math. Soc. **33** (1972), 455-462

MSC:
Primary 30A76

Erratum:
Proc. Amer. Math. Soc. **42** (1974), 647.

MathSciNet review:
0293088

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Abstract: Let be the class of functions , normalized so that which are regular in and have positive real part there. We obtain the minimum (maximum) real part of for fixed and and *P* running over the class .

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DOI:
https://doi.org/10.1090/S0002-9939-1972-0293088-5

Keywords:
Functions with positive real part,
region of variability,
variational formula

Article copyright:
© Copyright 1972
American Mathematical Society