Meromorphic Function Sharing Two Small Functions with Its Derivative

• Journal title : Kyungpook mathematical journal
• Volume 49, Issue 2,  2009, pp.235-243
• Publisher : Department of Mathematics, Kyungpook National University
• DOI : 10.5666/KMJ.2009.49.2.235
Title & Authors
Meromorphic Function Sharing Two Small Functions with Its Derivative
Liu, Kai; Qi, Xiao-Guang;

Abstract
In this paper, we deal with the problem of uniqueness of meromorphic functions that share two small functions with their derivatives, and obtain the following result which improves a result of Yao and Li: Let f(z) be a nonconstant meromorphic function, k > 5 be an integer. If f(z) and g(z) = $\small{a_1(z)f(z)+a_2(z)f^{(k)}(z)}$ share the value 0 CM, and share b(z) IM, $\small{\overline{N}_E(r,f=0=F^{(k)})=S(r)}$, f$\small{{\equiv}}$g, where $\small{a_1(z)}$, $\small{a_2(z)}$ and b(z) are small functions of f(z).
Keywords
meromorphic function;uniqueness;sharing values;
Language
English
Cited by
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