Rezumat articol ediţie STUDIA UNIVERSITATIS BABEŞ-BOLYAI

În partea de jos este prezentat rezumatul articolului selectat. Pentru revenire la cuprinsul ediţiei din care face parte acest articol, se accesează linkul din titlu. Pentru vizualizarea tuturor articolelor din arhivă la care este autor/coautor unul din autorii de mai jos, se accesează linkul din numele autorului.

 
       
         
    STUDIA MATHEMATICA - Ediţia nr.3 din 2018  
         
  Articol:   MEROMORPHIC FUNCTIONS WITH SMALL SCHWARZIAN DERIVATIVE.

Autori:  VIBHUTI ARORA, SWADESH KUMAR SAHOO.
 
       
         
  Rezumat:  
 We consider the family of all meromorphic functions f of the form

analytic and locally univalent in the puncture disk D0 := {zC : 0 < |z| < 1}. Our first objective in this paper is to find a sufficient condition for f to be meromorphically convex of order α, 0 ≤ α < 1, in terms of the fact that the absolute value of the well-known Schwarzian derivative Sf(z) of f is bounded above by a smallest positive root of a non-linear equation. Secondly, we consider a family of functions g of the form g(z) = z + a2z2 + a3z3 + ··· analytic and locally univalent in the open unit disk D := {zC : |z| < 1}, and show that g is belonging to a family of functions convex in one direction if |Sg(z)| is bounded above by a small positive constant depending on the second coefficient a2. In particular, we show that such functions g are also contained in the starlike and close-to-convex family.

Mathematics Subject Classification (2010): 30D30, 30C45, 30C55, 34M05. 
Keywords: Meromorphic functions, convex functions, meromorphically convex functions, close-to-convex functions, starlike functions, Schwarzian derivative.

 
         
     
         
         
      Revenire la pagina precedentă