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This book presents and extends methods for solving different types of strong nonlinearities encountered in engineering systems. Each chapter introduces a distinct approximate method, accompanied by representative examples from various fields of engineering.

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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.

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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.

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