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Linear differential equations (systems) with constant
coefficients.
The most efficient tool for these equations is the Laplace
transform defined by:
Example: solve
.
Apply
,
since:
we get:
hence:
since
.
This method is implemented by the LDEC
instruction. It takes
the second member at level 2 (here
),
and the characteristic equation at level 1 (here x+2) and returns
the solution vanishing at the origin at level 1, the characteristic
equation at level 2, and 1 at level 3. Be sure that the current variable
name contained in VX
is the right one!
Bernard Parisse
1998-07-31