Direction Field
> DOMAIN := t = 0 .. 2 ; # specify reasonable interval for indep vars
> WINDOW := y = -2 .. 2,
> v = -2 .. 2 ; # specify reasonable intervals for all dependent vars
>
> DIRplot := DEplot( MODEL, VAR, DOMAIN, WINDOW, arrows = MEDIUM,
> title = `Direction Field for #14(a)` ):
> DIRplot;
>