User Manual

5-49
• When “On” is selected “ΣDisplay” on the Setup screen and all three of the expressions
you input in the Recursion mode are selected for table creation, use the function menu
that appears when you press 3(PHASE) on the table screen to specify which two of the
expressions you want to use, and to specify whether you want to use numeric sequence
data or numeric sequence sum data.
1(
a • b ) ..........Graph using number sequences a
n
(
a
n
+1
, a
n
+2
) and b
n
( b
n
+1
, b
n
+2
)
2(
b • c ) ..........Graph using number sequences b
n
( b
n
+1
, b
n
+2
) and c
n
( c
n
+1
, c
n
+2
)
3(
a • c ) ..........Graph using number sequences a
n
( a
n
+1
, a
n
+2
) and c
n
( c
n
+1
, c
n
+2
)
4( Σ
a • b ) .......Graph using the sums of number
sequences a
n
( a
n
+1
, a
n
+2
) and b
n
( b
n
+1
, b
n
+2
)
5( Σ
b • c ) .......Graph using the sums of number
sequences b
n
( b
n
+1
, b
n
+2
) and c
n
( c
n
+1
, c
n
+2
)
6( Σ
a • c ) .......Graph using the sums of number
sequences a
n
( a
n
+1
, a
n
+2
) and c
n
( c
n
+1
, c
n
+2
)
k WEB Graph (Convergence, Divergence)
y = f ( x ) is graphed by presuming a
n
+1
= y , a
n
= x for linear two-term recursion a
n
+1
= f ( a
n
)
composed of a
n
+1
, a
n
. Next, it can be determined whether the function is convergent or
divergent.
1. From the Main Menu, enter the Recursion mode.
2. Configure V-Window settings.
3. Select 2-term recursion as the recursion formula type, and input the formula.
4. Specify the table range,
n start and end points, initial term value, and pointer start point.
5. Display the recursion formula number table.
6. Draw the graph.
7. Press w, and the pointer appears at the start point you specified.
Press w several times.
If convergence exists, lines that resemble a spider web are drawn on the display. Failure
of the web lines to appear indicates either divergence or that the graph is outside the
boundaries of the display screen. When this happens, change to larger V-Window values
and try again.
You can use fc to select the graph.