ABSTRACT
For a class of non homogeneous linear second order difference equations with non-constant coefficients, an elementary method for obtaining the general solution is given.
The basic idea of our method is to reduce the solution of a second order difference equation to the solution of two first order nonhomoge-neous difference equations.
Two examples, taken from a recent monograph [1], are also treated in order to illustrate the simplicity as well as the limits of our method in comparison with the general method described and used in [2]. The last one is based on the discrete Green functions and on the a priori knowledge of two linearly independent solutions of the homogeneous equation associated to the given difference equation.
Having in view the analogy between difference and differential equations our method may also be adopted to solve a special class of differential equations.
