Graphing Inequalities - Texas Instruments TI-80 Manual Book

Graphing Inequalities

Examine the inequality
explore the values of X where the inequality is true and where it is false.
Procedure
11-14 Applications
. .
4Xòì3X+5< 2X+4 graphically. Use the TEST functions to
1. Press 3. Select
settings. Press 2 ", and turn off all stat plots.
2. Press (, and turn off all functions. Enter the left side of
the inequality as
of the inequality as
false.
3. Press ), and enter these Window variable values.
Xmin=ë10
Xmax=10
Xscl=5
4. Press +. Press 8 8 to move to
inequality, observing the value of X.
and is 0 when
Y3
5. Press ( and turn off
only the inequality.
6. Press +. Notice that the values of
where the inequality is false.
DOT , SIMUL , and the default mode
Y1 , the right side as
Y3 . Y3 evaluates to 1 if true and 0 if
Ymin=ë10
Ymax=10
Yscl=5
.
Y1 Y2
Y1 and Y2 . Enter equations to graph
Y2 , and the statement
. Trace the
Y3
is 1 when
Y3 Y1
and are zero
Y3 Y4
,
Y2