Chapter 3: Function Graphing
82
To use
ZBox
to define another box within the new graph, repeat steps 2 through 4. To cancel
ZBox
, press
‘
.
Zoom In, Zoom Out
Zoom In
magnifies the part of the graph that surrounds the cursor location.
Zoom Out
displays a
greater portion of the graph, centered on the cursor location. The
XFact
and
YFact
settings
determine the extent of the zoom.
To zoom in on a graph, follow these steps.
1. Check
XFact
and
YFact
; change as needed.
2. Select
2:Zoom In
from the
ZOOM
menu. The zoom cursor is displayed.
3. Move the zoom cursor to the point that is to be the center of the new viewing window.
4. Press
Í
. The TI-83 Plus adjusts the viewing window by
XFact
and
YFact
; updates the
window variables; and replots the selected functions, centered on the cursor location.
5. Zoom in on the graph again in either of two ways.
•
To zoom in at the same point, press
Í
.
•
To zoom in at a new point, move the cursor to the point that you want as the center of the
new viewing window, and then press
Í
.
To zoom out on a graph, select
3:Zoom Out
and repeat steps 3 through 5.
To cancel
Zoom In
or
Zoom Out
, press
‘
.
ZDecimal
ZDecimal
replots the functions immediately. It updates the window variables to preset values, as
shown below. These values set
@
X
and
@
Y
equal to 0.1 and set the X and Y value of each pixel to
one decimal place.
ZSquare
ZSquare
replots the functions immediately. It redefines the viewing window based on the current
values of the window variables. It adjusts in only one direction so that
@
X=
@
Y
, which makes the
graph of a circle look like a circle.
Xscl
and
Yscl
remain unchanged. The midpoint of the current
graph (not the intersection of the axes) becomes the midpoint of the new graph.
Xmin=
L
4.7
Xmax=4.7
Xscl=1
Ymin=
L
3.1
Ymax=3.1
Yscl=1
