Texas Instruments TI-82 Getting Started page 21

The TI-82 is capable of shading the region above or below a graph or between two graphs. For example, to
y ≥ x
2
graph 1, first graph the function
Y- 1 1 , 10 , 2 ) ENTER (see Figure I.63). These keystrokes instruct the TI-82 to shade the region
VARS
2
above y x 1 and below
shading resolution value of 2. The result is shown in Figure I.64.
To clear the shading, press 2nd DRAW 1.
Figure I.63: DRAW Shade
Now use shading to solve the previous inequality,
lower boundary is named first in the SHADE command (see Figure I.65). To enter this in your TI-82, press
these keys: 2nd DRAW 7 X,T,
left from x 2, so the solution to
Figure I.65: DRAW Shade command
More information about the DRAW menu is in the TI-82 manual.
I.4 Trigonometry
I.4.1 Degrees and Radians: The trigonometric functions can be applied to angles measured either in radians
or degrees, but you should take care that the TI-82 is configured for whichever measure you need. Press
MODE to see the current settings. Press
angle measure is selected. Then press
cursor is on the measure you want, press ENTER to select it. Then press CLEAR or 2nd QUIT to leave the
mode menu.
Technology Guide
Graphing
2
y x
y 10 (chosen because this is the greatest
1
4 , 1 3 X,T,
3x
≥
1 x 4 is
2
twice and move down to the third line of the mode menu where
or to move between the displayed options. When the blinking
Copyright © by Houghton Mifflin Company. All rights reserved.
1 as Y . Then press 2nd DRAW 7 [Shade(] 2nd
1
y- value in the graph window) with
10
−10
−10
Figure I.64: Graph of
3x
≥
x 4. The function whose graph forms the
2
2 , 2 ) ENTER (Figure I.66). The shading extends
x ≤ 2,
or , 2 (see Figure I.66).
10
−10
−10
Figure I.66: Graph of
10
y ≥ x
2
1
10
3x
≥
1 x 4
2
I-21