This book presents and extends different known methods to solve different types of strong nonlinearities encountered by engineering systems. A better knowledge of the classical methods presented in the first part lead to a better choice of the so-called "base functions". These are absolutely necessary to obtain the auxiliary functions involved in the optimal approaches which are presented in the second part.
Every chapter introduces a distinct approximate method applicable to nonlinear dynamical systems. Each approximate analytical approach is accompanied by representative examples related to nonlinear dynamical systems from various fields of engineering.

Zusammenfassung
This book presents and extend different known methods to solve different types of strong nonlinearities encountered by engineering systems. A better knowledge of the classical methods presented in the first part lead to a better choice of the so-called base functions. These are absolutely necessary to obtain the auxiliary functions involved in the optimal approaches which are presented in the second part.
Every chapter introduces a distinct approximate method applicable to nonlinear dynamical systems. Each approximate analytical approach is accompanied by representative examples related to nonlinear dynamical systems from to various fields of engineering.

Inhalt
Introduction.- Perturbation method (Lindstedt-Poincaré).- The method of harmonic balance.- The method of Krylov and Bogolyubov.- The method of multiple scales.- The optimal homotopy asymptotic method.- The optimal homotopy perturbation method.- The optimal variational iteration method.- Optimal parametric iteration method.