Example 2. Use the
matrix exponential to find the general solution for the system of D.
E.'s
Solution 2.
First, write the system in vector and matrix
form
.
![[Graphics:../Images/MatrixExponentialMod_gr_152.gif]](../Images/MatrixExponentialMod_gr_152.gif)
A fundamental matrix solution is
.
![[Graphics:../Images/MatrixExponentialMod_gr_155.gif]](../Images/MatrixExponentialMod_gr_155.gif)
The matrix exponential is
.
![[Graphics:../Images/MatrixExponentialMod_gr_158.gif]](../Images/MatrixExponentialMod_gr_158.gif)
The solution to the D. E. with initial
conditions
, is
.
![[Graphics:../Images/MatrixExponentialMod_gr_162.gif]](../Images/MatrixExponentialMod_gr_162.gif)
![[Graphics:../Images/MatrixExponentialMod_gr_164.gif]](../Images/MatrixExponentialMod_gr_164.gif)
We are done.
Aside. We compare the
above work, with the construction of
using
Mathematica's subroutine MatrixExp.
![[Graphics:../Images/MatrixExponentialMod_gr_168.gif]](../Images/MatrixExponentialMod_gr_168.gif)
(c) John H. Mathews 2004