196 14 Special Transformations
Then, the unique solution is y(t) = etAyo +p(t), where
etAyo
2e* + e"
2e< - e~
and
p(t) =
/ 0 V (e~u + ue"") + e-'(e~" - ue-")] du
/o [e'(e-" + we"") + e^e"" + we" du
Then, after integration we have
p(t) =
-2 v(t)
3et-t
3e*-2
One can sotoe i/ie akwe differential equation system using Laplace trans-
forms:
y'(t) = Ay(t) + f(t)^s
<£>
s -1
-1 s
»i(s)~
*7i(«)
01
10
l
^i(s)
(*)
i i
i
Then, the resolvent matrix is
(sI-A)-^
1
(s-l)(s + l
If we multiply both sides of (*) 6y (**), we /wroe
s 1
1 s
(**)
T](S) =
T)(s)
1
(s-i)(s + i) L
I
s-l +
3s+ 1
s + 3
1
y(*) =
- s^2 (s-l)(s + l)
1
s^2 + l
2s
0
-2
3e(-£
3e' -2
In order to find e , we expand right hand side of (•*) as
n(s) =
["1
2
1
L2
ll
2
1
1 i i 2 J
+ s + 1 •\ 2-
If we invert it, we will have the following
•" = £
e* + e * el — e *