Some subclasses of close-to-convex functions

Adam Lecko

Adam Lecko

Annales Polonici Mathematici, Tome 58 (1993), p. 53-64 / Harvested from The Polish Digital Mathematics Library

Résumé

For α ∈ [0,1] and β ∈ (-π/2,π/2) we introduce the classes $C_{β} (α)$ defined as follows: a function f regular in U = z: |z| < 1 of the form $f (z) = z + \sum_{n = 1}^{\infty} a_{n} z^{n}$ , z ∈ U, belongs to the class $C_{β} (α)$ if $R e e^{i β} (1 - α ² z ²) f^{'} (z) < 0$ for z ∈ U. Estimates of the coefficients, distortion theorems and other properties of functions in $C_{β} (α)$ are examined.

Publié le : 1993-01-01

Zbl 0776.30011

EUDML-ID : urn:eudml:doc:262387

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     title = {Some subclasses of close-to-convex functions},
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     volume = {58},
     year = {1993},
     pages = {53-64},
     zbl = {0776.30011},
     language = {en},
     url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-apmv58z1p53bwm}
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Adam Lecko. Some subclasses of close-to-convex functions. Annales Polonici Mathematici, Tome 58 (1993) pp. 53-64. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-apmv58z1p53bwm/

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