c) Direction Field

> ode1 := diff( x(t), t ) = 3*x(t) + 2*y(t) :

> ode2 := diff( y(t), t ) = - 2*y(t) :

> MODEL := [ ode1, ode2 ] ;

> VAR := { x(t), y(t) } ;

>

> DOMAIN := t = 0 .. 5 ;

> WINDOW := x = -3 .. 3,

> y = -3 .. 3 ;

>

> IC := [ [x(0)= 0.03,y(0)=0],

> [x(0)=-0.03,y(0)=0],

> [x(0)=-1,y(0)= 2.5],

> [x(0)= 1,y(0)=-2.5] ];

> PHASEplot := DEplot( MODEL, VAR, DOMAIN, WINDOW, IC, arrows = MEDIUM,

> title = `Direction Field & Straight-Line Solutions for #1` ):

> PHASEplot;