Second Order Linear Differential Polynomials and Real Meromorphic Functions |
| |
Authors: | J K Langley |
| |
Institution: | 1. School of Mathematical Sciences, University of Nottingham, Nottingham, NG7 2RD, UK
|
| |
Abstract: | The main result determines all real meromorphic functions f of finite lower order in the plane such that f has finitely many zeros and non-real poles, while f′′ + a 1 f′ + a 0 f has finitely many non-real zeros, where a 1 and a 0 are real rational functions which satisfy a 1(∞) = 0 and a 0(x) ≥ 0 for all real x with |x| sufficiently large. This is accomplished by refining some earlier results on the zeros in a neighbourhood of infinity of meromorphic functions and second order linear differential polynomials. Examples are provided illustrating the results. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|