Article Contents
Article Contents

# On quasi-periodic perturbations of hyperbolic-type degenerate equilibrium point of a class of planar systems

• In this paper we consider two-dimensional nonlinear quasi-periodic system with small perturbations. Assume that the unperturbed system has a hyperbolic-type degenerate equilibrium point and the frequency satisfies the Diophantine conditions. Using the KAM iteration we prove that for sufficiently small perturbations, the system can be reduced by a nonlinear quasi-periodic transformation to a suitable normal form with an equilibrium point at the origin. Hence, for the system we can obtain a small quasi-periodic solution.
Mathematics Subject Classification: Primary: 34J40, 34C27; Secondary: 34E20.

 Citation:

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