Access the full text.
Sign up today, get DeepDyve free for 14 days.
References for this paper are not available at this time. We will be adding them shortly, thank you for your patience.
DEMONSTRATIO MATHEMATICAVol. XXXIIINo 12000Virgil PescarN E W CRITERIA FOR UNIVALENCEOF CERTAIN INTEGRAL OPERATORSAbstract. In this work there is considered the class of univalent functions defined bythe condition I 'AS"? — l | < 1, |z| < 1, where f(z) = z + a.2z2 + . . . is analytic in the unitI / (z)Idisc U = {z : \z\ < 1}. The author determines conditions for the univalence of certainintegral operators.1. IntroductionWe denote by S the class of regular and univalent functions f(z) =z + a^z2 + . . . in the unit disc U. Let A be the class of functions f which areanalytic in the unit disc U with /(0) = /'(0) — 1 = 0.In their paper [2] Ozaki and Nunokawa proved the followingTHEOREMA. Assume that f € A satisfies the conditionz2f'{z)(1)- 1f2(z)< l,zeu,then f is univalent in U.2. Preliminary resultsWe shall use the following results.THEOREMB [3]. Let a be a complex number, Rea > 0 and f € A. If(2)1 -|2|2*eaReafor all z €U, then the functionzf"(z)< 1z(3)is in the class S.Fa(z)=[a\ua~1f'(u)du52V. PescarTHEOREM C [4]. Let a be a complex number, Rea > 0 and f(z) = z +CI2Z2 + ... is a regular function
Demonstratio Mathematica – de Gruyter
Published: Jan 1, 2000
Read and print from thousands of top scholarly journals.
Already have an account? Log in
Bookmark this article. You can see your Bookmarks on your DeepDyve Library.
To save an article, log in first, or sign up for a DeepDyve account if you don’t already have one.
Copy and paste the desired citation format or use the link below to download a file formatted for EndNote
Access the full text.
Sign up today, get DeepDyve free for 14 days.
All DeepDyve websites use cookies to improve your online experience. They were placed on your computer when you launched this website. You can change your cookie settings through your browser.