' - - File:XIVa   ' 2nd Order differential equation.
' Equation:  X''(t) - 2a*X'(t) + (w^2 + a^2)*x = 0  
' Rewritten:  X''(t) = 2a*X'(t) - (w^2 + a^2)*x

' FORMAT:  F{t,x,x'} is Mode 1 and 
'                    a system:  X'{t} = F{t,x,y}
'                                      Y'{t} = G{t,x,y}  is Mode 2.
' See Walk Thru documents how to choose which mode.
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F{t,x,y} = y                                        ' F{t, x, x');  set y = x';
G{t,x,y} = 2a*y - (w^2 + a^2)x         ' then G{t,x,y} becomes X''{t}.
'Recall: We cannot use 2ay; ay becomes a 2-symbol const. ID. See page 3 of WalkThru.
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a = -.20:  w = 3
to =0 :  tf = 8  :  yo =0  :  yp = w

IVP[F,G, {to, tf, yo, yp}{1.00,  0.02,1}] 


