e=10;l=50; modell:={x'[t]==y[t]-e (x[t]^3/3-x[t]), y'[t]==-x[t], x[0]==2, y[0]==0 }; loesung=NDSolve[modell,{x,y},{t,0,l},MaxSteps->3000]; abb=Plot[Evaluate[{x[t],y[t]}/.loesung],{t,0,l}, PlotRange->All,PlotPoints->2000, AxesLabel->{"t","x,y"},ImageSize->{400,300}, PlotStyle->{{},{Dashing[{0.01}]}}];