Texas Instruments TI-86 - Manual (Page 105)

Chapter 6: Graph Tools
93
06TOOLS.DOC TI-86, Chap 6, US English Bob Fedorisko Revised: 02/13/01 2:23 PM Printed: 02/13/01 3:01 PM Page 93 of 22 06TOOLS.DOC TI-86, Chap 6, US English Bob Fedorisko Revised: 02/13/01 2:23 PM Printed: 02/13/01 3:01 PM Page 93 of 22
Defining a Custom Zoom In
Using BOX , you can zoom in on any rectangular area within the current graph screen.
ᕡ Select BOX from the GRAPH ZOOM menu. The
zoom cursor is displayed at center screen.
ᕢ Move the cursor to any spot you want to define
as a corner of the zoom box; mark the corner
with a small square.
6 (
&
" # ! $
b
ᕣ Move the cursor away from the first corner,
creating an adjustable box whose diagonal
corners are the small square and the cursor.
ᕤ When you have defined the box, replot all
selected functions in the new graph screen.
ᕥ Clear the menus from the screen.
" # ! $
b
:
Setting Zoom Factors
Zoom factors define the magnification or reduction factor by which ZIN , ZOUT , ZOOMX , and
ZOOMY zoom in or zoom out around a point. To display the zoom factors editor, select
ZFACT from the GRAPH ZOOM menu (press 6 ( / / '). xFact and yFact must
be ‚ 1. The default value for both factors is 4 in all graphing modes.
Zooming In and Zooming Out on a Graph
ZIN magnifies the part of the graph surrounding the cursor location. ZOUT displays a greater
portion of the graph, centered on the cursor location. xFact and yFact determine the extent.
The steps below describe how to use ZIN . To use ZOUT , select it instead of ZIN in step 2.
Before you begin these
steps, enter a function in the
equation editor. In the
example, the function
y(x)=x^3+.3x
2 N 4x is graphed.
To cancel BOX without
redefining the graph screen,
press
: .
When you replot the graph,
the TI
- 86 updates the window
variable values.
To store to xFact or yFact
from the home screen or in
the program editor, you can
select it from the VARS ALL
screen or enter it using
ALPHA and alpha keys.