The linear differential equations with complex constant coefficients and Schrödinger equations

We investigate some properties of approximate solutions for the second-order inhomogeneous linear differential equations, y′′(x)+αy′(x)+βy(x)=r(x), with complex constant coefficients. And, as an application of our results, we will see the time independent Schrödinger equations. This paper was motivated by the paper, Li and Shen (2010).