Hi
I have been trying to solve some 2nd order ordinary diff equation with
constant coefficients using maxima. For some reason it is not working
for the diff eqation given below:
y" + a* y' + b*y = c*x
For the case 4*b^2-a=0 I get a wrong answer and for the case 4*b^2-a
>0 ,the error I get is
" Quotient by a polynomial of higher degree
-- an error. Quitting. To debug this try DEBUGMODE(TRUE);)"
The maxima run is shown below:
Maxima version: 5.9.0
Maxima build date: 15:50 9/25/2003
host type: i686-pc-cygwin
lisp-implementation-type: CLISP
lisp-implementation-version: 2.31 (released 2003-09-01) (built 3272325060) (
ry 3273508250)
(D5)
(C6) 'diff(y,x,2) + a*y = c* x;
2
d y
(D6) --- + a y = c x
2
dx
(C7) ode2(d6,y,x);
Is a positive, negative, or zero?
positive;
c x
(D7) y = %K1 SIN(SQRT(a) x) + %K2 COS(SQRT(a) x) + ---
a
(C8) 'diff(y,x,2) + a*'diff(y,x) + b*y = c*x;
2
d y dy
(D8) --- + a -- + b y = c x
2 dx
dx
(C9) ode2(d8,y,x);
2
Is 4 b - a positive, negative, or zero?
zero;
a x
- ---
2 4 a c x - 16 c
(D9) y = (%K2 x + %K1) %E + --------------
3
a
(C10) ode2(d8,y,x);
2
Is 4 b - a positive, negative, or zero?
positive;
Quotient by a polynomial of higher degree
-- an error. Quitting. To debug this try DEBUGMODE(TRUE);)
(C11)
Is there anything I am not doing correctlty.
Thanks
--
*Javed Alam, *Ph.D.
*Professor*
*Civil/Environmental/Chemical Engineering Department*
Youngstown State University
Youngstown, Ohio 44555
Phone 330-941-3029
Fax 330-941-3265
e-mail jalam@cc.ysu.edu <mailto:jalam@cc.ysu.edu>;
web: http://www.eng.ysu.edu/~jalam/ <http://www.eng.ysu.edu/%7Ejalam/>;
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