' - - File: XVIIc 
'     X''' + 3X'' + 3X' + X = 0

F{t,x,y,z} = y
G{t,x,y,z} = z
H{t,x,y,z} = -3z - 3y - x

to = 0 : tf = 8
c1 = 1: c2 = 3 : c3 = 4
xo = c1
yo = -c1 + c2
zo = c1 - 2c2 + 2c3

IVP[F,G,H, {to, tf, xo, yo, zo} { 1.05,  0.05, 2}]

' - - - - - - - - - - - - - - - - - Plot known solution for comparision. - - - - - - - - - - - - - - - - - -
X{t} = c1*Exp[-t] +  c2*t*Exp[-t] + c3*t^2*Exp[-t]
V<t> = <t, X, 0>

tx = 0.1 : ty = 0 : tz = 0         ' We translate the t-axis a small amout to see the match.
U<t> = vTran[V, tx,ty,tz]        ' Otherwise, Plot vector V instead.

Plot[U, {t, to, tf, 100}]


