“…Liao [15,16] has developed this purely analytic technique to solve nonlinear problems in science and engineering. The HAM has been applied successfully to many nonlinear problems such as free oscillations of self-excited systems [17], the generalized Hirota-Satsuma coupled KdV equation [18], heat radiation [19], finding the root of nonlinear equations [20], finding solitary-wave solutions for the fifth-order KdV equation [21], finding solitary wave solutions for the Kuramoto-Sivashinsky equation [22], finding the solitary solutions for the Fitzhugh-Nagumo equation [23], boundary-layer flows over an impermeable stretched plate [24], unsteady boundarylayer flows over a stretching flat plate [25], exponentially decaying boundary layers [26], a nonlinear model of combined convective and radiative cooling of a spherical body [27], and many other problems (see [28,29,30,31,32,33,34,35,36], for example).…”