# The Variable Odetype - HP 49g+ User Manual

Graphing calculator.

In the calculator use:
'd1y(x)+x^2*y(x)=5' ` 'y(x)' ` DESOLVE
The
solution
(INT(5*EXP(xt^3/3),xt,x)+cC0)*1/EXP(x^3/3))' }, i.e.,
(
)
y
x

## The variable ODETYPE

You will notice in the soft-menu key labels a new variable called @ODETY
(ODETYPE). This variable is produced with the call to the DESOL function and
holds a string showing the type of ODE used as input for DESOLVE. Press
@ODETY to obtain the string "
Example 2 -- Solve the second-order ODE:
In the calculator use:
'd1d1y(x)+x*d1y(x) = EXP(x)' ` 'y(x)' ` DESOLVE
The result is an expression having two implicit integrations, namely,
For this particular equation, however, we realize that the left-hand side of the
equation represents d/dx(x dy/dx), thus, the ODE is now written:
and
2
⋅y(x) = 5.
dy/dx + x
provided
3
exp(
/
) 3
5
exp(
x
".
1st order linear
2
2
d
y/dx
+ x (dy/dx) = exp(x).
d/dx(x dy/dx ) = exp x,
x dy/dx = exp x + C.
is
{'y
3
/
) 3
.
x
dx
cC
0
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=