On starlikeness of certain integral transforms
S. Ponnusamy
Annales Polonici Mathematici, Tome 57 (1992), p. 227-232 / Harvested from The Polish Digital Mathematics Library
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Let A denote the class of normalized analytic functions in the unit disc U = z: |z| < 1. The author obtains fixed values of δ and ϱ (δ ≈ 0.308390864..., ϱ ≈ 0.0903572...) such that the integral transforms F and G defined by F(z)=∫0z(f(t)/t)dt and G(z)=(2/z)∫0zg(t)dt are starlike (univalent) in U, whenever f ∈ A and g ∈ A satisfy Ref’(z) > -δ and Re g’(z) > -ϱ respectively in U.

Publié le : 1992-01-01
EUDML-ID : urn:eudml:doc:262314 
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S. Ponnusamy. On starlikeness of certain integral transforms. Annales Polonici Mathematici, Tome 57 (1992) pp. 227-232. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-apmv56z3p227bwm/

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