Texas Instruments TI-89 Titanium

Sequence Graphing 355
Example: Oscillation
This example shows how the initial value can affect a sequence.
1. On the Y= Editor (8#), use the same sequence defined in the divergence
example: u1(n) = 3.2u1(nN1) N .8(u1(nN1))
2
. Set initial value ui1 = 0.5.
2. Set
Axes = TIME.
3. On the Window Editor (8$), set the Window variables.
5. On the Y= Editor, set
Axes = WEB and Build Web = AUTO.
7. Regraph the sequence.
The web plot shows how quickly the
sequence diverges to large negative
values.
nmin=1
nmax=100
plotstrt=1
plotstep=1
xmin=0
xmax=100
xscl=10
ymin=0
ymax=5
yscl=1
4. Graph the sequence (8%).
Note: Compare this graph with the
divergence example. This is the same
sequence with a different initial value.
y=3.2xN.8x
2
u(nN1)
u(n
y=x
u(n)
n