Original Article
Kyungpook Mathematical Journal 2013; 53(4): 541-552
Published online December 23, 2013
Copyright © Kyungpook Mathematical Journal.
Zeros and Uniqueness of Difference Polynomials of Meromorphic Functions
Xiaoguang Qi1, Jia Dou2
1University of Jinan, School of Mathematics, Jinan, Shandong, 250022, P. R. China
2Quancheng Middle School, Jinan, Shandong, 250000, P. R. China
This research is a continuation of a recent paper due to the first author in [9]. Different from previous results, we investigate the value distribution of difference polynomials of moromorphic functions in this paper. In particular, we are interested in the existence of zeros of ƒ(z)n(λƒ(z+c)m+μf(z)m)–a, where f is a moromorphic function, n, m are two non-negative integers, and λ,μ are non-zero complex numbers. However, the proof here is obviously different to the one in [9]. We also study difference polynomials of entire functions sharing a common value, which improves the result in [10, 13].
Keywords: meromorphic functions, uniqueness, difference, shift, value distribution, sharing value