Geometric properties of solutions of a class of differential equations

The main object of this paper is to investigate several geometric properties of the solutions of the following second-order linear differential equation: w″(z)+a(z)w′(z)+b(z)w(z)=0, where the functions a(z) and b(z) are analytic in the open unit disk U. Relevant connections of the results presented in this paper with those given earlier by, for example, Robertson, Miller and Saitoh are also considered.