This research article is concerned with the solution of hydrodynamic stability based linear and nonlinear fourteenth order differential
problem, which has great significance in applied physics, astrophysics,
applied mathematics, engineering departments. The homotopy perturbation method (HPM) and optimal homotopy asymptotic method (OHAM)
are applied for the solution of the existed problem. These semi analytical
techniques are continuously evolved to solve diverse range of linear and
nonlinear problems with effective approximate agents which is a rapid approach to the exact solutions. This approach is effectively proposed with
different numerical examples, which are taken from literature. Numerical results are accomplished by phrase of convergent series solutions and
approach to the accurate solutions only by taking minimum steps. The numerical results are exercised with exact solutions, cubic polynomial spline
technique (CPST) and cubic non-polynomial spline technique (CNPST),
excellent agreement has been observed. The observations suggested that
OHAM and HPM performed excellent in comparison to the CPST and
CNPST in terms of solution, which demonstrated the effectiveness, potential and validity of suggested schemes in reality and acquired results
are of top-level perfection.