User Manual

Chapter 17: Activities 302
Setting the Viewing Window
You also can use the graphing features of the TI-84 Plus to find the maximum value of a previously
defined function. When the graph is activated, the viewing window defines the displayed portion of
the coordinate plane. The values of the window variables determine the size of the viewing
window.
7. Press † or } to move the cursor to
3.67.
Press ~ to move the cursor into the
Y1
column.
The value of
Y1 at X=3.67 is displayed on
the bottom line in full precision as
410.261226.
8. Press † to display the other maximum.
The value of
Y1 at X=3.68 in full precision
is
410.264064, at X=3.69 is 410.262318 and
at
X=3.7 is 410.256.
The maximum volume of the box would
occur at
3.68 if you could measure and
cut the paper at .01-centimeter
increments.
1. Press p to display the window
editor, where you can view and edit the
values of the window variables.
The standard window variables define
the viewing window as shown.
Xmin,
Xmax, Ymin, and Ymax define the
boundaries of the display.
Xscl and Yscl
define the distance between tick marks
on the
X and Y axes. Xres controls
resolution.
2. Press
0 Í to define Xmin.
3. Press
20 ¥ 2 to define Xmax using an
expression.
Note: For this example, the division sign
is used for the calculation. However, you
can use n/d entry format where fraction
output can be experienced, depending
on mode settings.