Successive complementary expansion method for solving Troesch's problem as a singular perturbation problem (Q277605)

Summary: A simple and efficient method that is called \textit{Successive Complementary Expansion Method (SCEM)} is applied for approximation to an unstable two-point boundary value problem which is known as Troesch's problem. In this approach, Troesch's problem is considered as a singular perturbation problem. We convert the hyperbolic-type nonlinearity into a polynomial-type nonlinearity using an appropriate transformation, and then we use a basic zoom transformation for the boundary layer and finally obtain a nonlinear ordinary differential equation that contains SCEM complementary approximation. We see that SCEM gives highly accurate approximations to the solution of Troesch's problem for various parameter values. Moreover, the results are compared with Adomian Decomposition Method (ADM) and Homotopy Perturbation Method (HPM) by using tables.