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Acta Mathematica Vietnamica

Zeros of Differential Polynomials of Meromorphic Functions

Ta Thi Hoai An , icon-email Nguyen Viet Phuong

Abstract

Let f be a transcendental meromorphic function on C,k be a positive integer, and Q0,Q1,,Qk be polynomials in C[z]. In this paper, we will prove that the frequency of distinct poles of f is governed by the frequency of zeros of the differential polynomial form Q0(f)Q1(f)Qk(f(k) in f. We will also prove that the Nevanlinna defect of the differential polynomial form Q0(f)Q1(f)Qk(f(k) in f satisfies aCδ(a,Q0(f)Q1(f)Qk(f(k)))1 with suitable conditions on k and the degree of the polynomials. Thus, our work is a generalization of Mues’s conjecture and Goldberg’s conjecture for the more general differential polynomials.