Sketch the graph of an updating function that has a corner at an equilibrium and is neither stable nor unstable.
The unusual equilibrium in the text has an updating function that lies below the diagonal both to the left and to the right of the equilibrium. There are several other ways that an updating function can be tangent to the diagonal at an equilibrium. In each case, cobweb starting from points to the left and to the right of the equilibrium, and describe the stability.