Let a,b ∈ z: 0<|z|<1 and let S(a,b) be the class of all univalent functions f that map the unit disk into {a,bwith f(0)=0. We study the problem of maximizing |f’(0)| among all f ∈ S(a,b). Using the method of extremal metric we show that there exists a unique extremal function which maps onto a simply connnected domain bounded by the union of the closures of the critical trajectories of a certain quadratic differential. If a<0
@article{bwmeta1.element.bwnjournal-article-cmv80i2p253bwm, author = {Dimitrios Betsakos}, title = {On bounded univalent functions that omit two given values}, journal = {Colloquium Mathematicae}, volume = {79}, year = {1999}, pages = {253-258}, zbl = {0937.30012}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-cmv80i2p253bwm} }
Betsakos, Dimitrios. On bounded univalent functions that omit two given values. Colloquium Mathematicae, Tome 79 (1999) pp. 253-258. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-cmv80i2p253bwm/
[000] [1] V. N. Dubinin, Symmetrization in the geometric theory of functions of a complex variable, Russian Math. Surveys 49 (1994), 1-79. | Zbl 0830.30014
[001] [2] W. K. Hayman, Multivalent Functions, 2nd ed., Cambridge Univ. Press, Cambridge, 1994.
[002] [3] J. A. Jenkins, On the existence of certain general extremal metrics, Ann. of Math. 66 (1957), 440-453. | Zbl 0082.06301
[003] [4] J. A. Jenkins, Univalent Functions and Conformal Mappings, Springer, Berlin, 1965.
[004] [5] J. A. Jenkins, A criterion associated with the schlicht Bloch constant, Kodai Math. J. 15 (1992), 79-81. | Zbl 0764.30018
[005] [6] G. V. Kuz'mina, Covering theorems for functions meromorphic and univalent within a disk, Soviet Math. Dokl. 3 (1965), 21-25.
[006] [7] G. V. Kuz'mina, Moduli of Families of Curves and Quadratic Differentials, Proc. Steklov Inst. Math. 139 (1982).
[007] [8] M. A. Lavrent'ev, On the theory of conformal mappings, Amer. Math. Soc. Transl. (2) 122 (1984), 1-63 (translation of Trudy Fiz.-Mat. Inst. Steklov. 5 (1934), 159-245).