In this paper, we investigate the admissible entire solutions of finite order of the differential-difference equations (f'(z))^{2}+P^{2}(z)f^{2}(z+c)=Q(z)e^{alpha(z)} and (f'(z))^{2}+[f(z+c)-f(z)]^{2}=Q(z)e^{alpha(z)}, where P(z), Q(z) are two non-zero polynomials, alpha(z) is a polynomial and cinmathbb{C}backslash{0}. In addition, we investigate the non-existence of entire solutions of finite order of the differential-difference equation (f'(z))^{n}+P(z)f^{m}(z+c)=Q(z), where P(z), Q(z) are two non-constant polynomials, cinmathbb{C}backslash{0}, m, n are positive integers and satisfy frac{1}{m}+frac{1}{n}<2 except for m=1, n=2.
Read full abstract