DEtools
ode_int_y
given the nth order linear ODE satisfied by y(x), compute the nth order linear ODE satisfied by int(y(x),x)
ode_y1
given the nth order linear ODE satisfied by y(x), compute the nth order linear ODE satisfied by diff(y(x),x)
Calling Sequence
Parameters
Description
Examples
ode_int_y(ode, y(x))
ode_y1(ode, y(x))
ode
-
ordinary differential equation satisfied by y(x)
y(x)
unknown function of one variable
Given a nth order linear ODE for yx, the ode_int_y and ode_y1 commands respectively compute the nth order linear ODE satisfied by ∫yxⅆx and ⅆⅆxyx.
For enhanced input output use DEtools[diff_table] and PDEtools[declare].
withDEtools,diff_table,ode_int_y,ode_y1
diff_table,ode_int_y,ode_y1
PDEtoolsdeclareprime=x,yx,cx
derivatives with respect toxof functions of one variable will now be displayed with '
yxwill now be displayed asy
cxwill now be displayed asc
Y≔diff_tableyx:
PDEtoolsdeclareyx,cx,prime=x
Now, if y satisfies
c0xY+c1xYx+c2xYx,x+Yx,x,x,x=0
c0y+c1y'+c2y''+y''''=0
then the derivative of y satisfies
DEtoolsode_y1=0
y''''−c0 'y'''c0+c2y''−c0 'c2−c1c0−c2 'c0y'c0−c0 'c1−c02−c1 'c0yc0=0
and so, the integral of the function y in the equation above satisfy this other ODE (the starting point)
DEtoolsode_int_y,yx=0
See Also
Download Help Document