Abstract University: King Khalid University College: College of Science Major: Functional Analysis Thesis Title: Approximation of the solution of a semilinear elliptic problem in an unbounded domain. Student's Name: Bushra Mohamad Taisir Albukaai Student's ID Number: 435822766 Date of Submission: 19/9/1438 H Abstract: Let be odd and twice continuously differentiable real function on the interval , with , and such that is strictly increasing over . Let be th