Publication: On the improvement of Mocanu's conditions
Date
2013-12
Authors
Nunokawa, M.
Owa, Shigeyoshi
Cho, N. E.
Sokół, J.
Yavuz Duman, Emel
Journal Title
Journal ISSN
Volume Title
Publisher
Springer International Publishing
Abstract
We estimate |Arg{p(z)}| for functions of the form p(z)=1+a1z+a2z2+a3z3+⋯ in the unit disc D={z:|z|<1} under several assumptions. By using Nunokawa’s lemma, we improve a few of Mocanu’s results obtained by differential subordinations. Some applications for strongly starlikeness and convexity are formulated.
Description
Keywords
Nunokawa’s lemma, strongly starlike functions of order alpha, strongly convex functions of order alpha, subordination