Abstract A survey of the relative efficiency of various approximate methods for solving the non-relativistic Schroedinger Equation [sic] is made. In particular, a comparison is made of the results obtained for the problem of a simple harmonic oscillator perturbed by λx∝, (∝ =3,4 ) while using the Rayleigh-Ritz variational principle, Linear Variation of Functions, and the Reyleigh-Schroedinger [sic]...