Abstract
In a recent paper, Moreno and Zepeda (1984) have applied the 1/N expansion to obtain an approximate analytic formula for the ground state energy of a particle bound by a Yukawa potential. Using the method of Mlodinow and Shatz (1982), the author calculates the energies of the ground state and the first excited state of the system to show that the results provided by the 1/N expansion are identical with those obtained by applying either the analytic perturbation theory or the hypervirial equations with the Hellman-Feynman theorem. Also an approximate analytic formula for the ground state energy is proposed.