(b)
The equilibrium solution
is a sink and
is a node. (The singular solution
is a source.)
![[Maple Math]](images/exam1-soln61.gif){kind=small}
is a sink and
![[Maple Math]](images/exam1-soln62.gif){kind=small}
is a node. (The singular solution
![[Maple Math]](images/exam1-soln63.gif){kind=small}
is a source.)
is a sink and
is a node. (The singular solution
is a source.)