In your worksheet you will
find commands for constructing a partial phase portrait of the van der
Pol system for parameter value a = 0.5. Add enough initial conditions
to get a complete phase portrait.
Describe the long-term
behavior of the system for this value of a. You should see something
happening that never happens with a linear system. This phenomenon
is called a limit cycle.
Plot the solution functions,
I(t) and V(t), as functions of time.
Repeat steps 1, 2, and
3 for a = 1.0, 1.5, 2.0, 2.5. Describe what changes as a
increases.
