Texas Instruments TI-89 Titanium Short User Manual page 70

Steps and keystrokes
2. Display and clear the
the 1st-order differential equation:
y1'(t)=.001y1...(100Ny1)
Press p to enter the ... shown above. Do not
use implied multiplication between the
variable and parentheses. If you do, it is
treated as a function call.
Leave the initial condition yi1 blank.
Note: With y1' selected, the device will
graph the y1 solution curve, not the
derivative y1'.
Press 8 # , 8 ¸ ¸ .001 Y1 p c
100 | Y1 d ¸
3. Display the
Then set
Axes = ON
Method = RK
Note: To graph one differential equation,
Fields must be set to
Fields=DIRFLD
graph.
@ 8 Í D D B 2 D D B 2 D B 1 D B 1
¸
4. Display the
Window variables as shown to the right.
Press 8 $ 0 D 10 D .1 D 0 D ? 10 D
110 D 10 D ? 10 D 120 D 10 D 0 D .001
D 20
5. Display the Graph screen.
Because you did not specify an initial
condition, only the slope field is drawn (as
specified by
dialog box).
FORMATS
Press 8 %
64
Y= Editor
GRAPH FORMATS
,
Labels = ON
, and
Fields = SLPFLD
SLPFLD
, an error occurs when you
Window Editor
Fields=SLPFLD
. Then define
dialog box.
,
Solution
.
or . If
FLDOFF
, and set the
in the
GRAPH
Display
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