ABSTRACT
In this chapter, we examine systems whose dynamics are described by giving a system of rst-order equations. Physical systems whose behavior consists of a number of interacting processes will oen have their dynamics described by a set of rst-order equations, with one equation describing each individual process. Usually, the eect of these processes on each other is provided by including interaction terms in the equations. is gives rise to a system of equations that must be simulated as a whole, since the interactions are simultaneous with the dynamics of the individual processes. As we will see in Chapter 9, higher-order dierential equations can be transformed into systems of rst-order equations, thereby producing another source of coupled rst-order equations.
