Create a list of all periodic points of f : $f (x) = x + sin x$ on R and use the graph of f to sketch its phase portrait. Identify the stable quantities for each of the periodic points.
What does the question mean?
"Create a list of all periodic points for f : $f (x) = x + sin x$ on $R$" ?
Then sketching the phase portrait, must be related to the actual periodic points one finds?
Thanks