8.4.1.1 Stability of the systems of equations

Problem: Investigate the stability of the system in at zeroresting point. \[ \left\{\begin{array}{c} \frac{d y}{d t}=-\sin y-x e^{-x} \\ \frac{d x}{d t}=\sin (-x)+\sin (-y) \end{array} .\right. \]