Activity TI 83 Using the Draw Menu

							Activity:

TI 83: Using the Draw Menu
Overview

The TI 83 calculator offers many different applications that help enhance math in the
classroom. The TI has the ability to multiply matrices, analyze statistics, but for today
we are just going to focus on some of the basic functions within the Draw menu of the
calculator. Specifically we are going to make line segments, tangent lines of functions,
and inverses of functions.

Getting Started

We are first going to turn the calculator on, in order to do this press the [ON] button
located at the bottom left corner of the calculator. After this step is completed we are
going to press the [MODE] button located near the top of the calculator. In order to
complete the task for today, we are going adjust are settings so that all of these settings
are highlighted.

Normal
Float
Radian
Func
Connected
Sequential
Full

If they are not currently highlighted you can use your arrows to move over the setting you
want, once it is highlighted or selected press enter. You can then follow the same steps
for each of the settings listed above. To get out of the [MODE] screen you press the
yellow [2nd] key and then press the [MODE] key, this will bring you back to the home
screen.

Next we are going to set up our window for a graph we are going to create later in the
lesson. To complete this you must press the blue [WINDOW] button located at top of the
calculator near the screen. Something similar to this will appear.

WINDOW
       Xmin= -20
       Xmax= 20
       Xscl= 1
       Ymin= -20
       Ymax= 20
       Yscl= 1
       Xres=1
In order adjust you max and min to the above, you can use your arrows to scroll up and
down to the number you have to adjust. Once you are there press the [CLEAR] button
and then you can enter the limits listed above. To leave this screen once again you can
press thee [2nd] key and then the [MODE] key.

Drawing Line Segments

There are two different ways to draw line segments

   1. Drawing the line segment directly on the graph

First you want to open up your graph screen by pressing the blue [GRAPH] key located
at the top of the calculator. After your screen has been opened, you can then open your
Draw menu, to do this you press the [2nd] key and then the [PRGM] key. You will then
have a screen that looks like this

DRAW POINTS          STO
1: ClrDraw
2: Line(
3: Horizontal
4: Vertical
5: Tangent(
6: DrawF
7: Shade(

Then you can either select the Line( option by scrolling down with your arrows or you
can simply press the number [2] on you calculator. This should bring you back to the
graph screen. Now what you want to do is move your cursor around using the arrows,
once you have gotten to your desired point you press the [ENTER] key. This will plot the
first point of your segment. Then you use your arrows to move to the second point, once
you have the cursor where you want the second point press the [ENTER] key. You can
continue to experiment with this function.

**If you would like to clear your drawing enter the Draw Menu by pressing the [2nd] key
and then the [PRGM] key. Once again you should receive a screen that looks like this


DRAW POINTS          STO
1: ClrDraw
2: Line(
3: Horizontal
4: Vertical
5: Tangent(
6: DrawF
7: Shade(
You can then scroll down with your arrows to select ClrDraw and then press enter or
simply press 1, this will give you a blank graph.

   2. Drawing a line segment from the home screen.

Before starting, clear your previous drawing.

First, you want to get back to the home screen by pressing [2nd] and then [MODE]. Then
you enter the Draw menu again and select 2:Line(. This should then bring you back to
the home screen. Line( should be displayed on the home screen, what you would like to
do next is enter in the end points of the line.

So you should enter in the points in this order Line(X1, Y1, X2, Y2
Once your points are in the right place you can hit [ENTER] and the graph screen will
appear with your line. In order to continue to draw lines in this manner you need to press
the [2nd] [MODE] key to exit the graph screen and then continue the same process from
the home screen.

Drawing Tangent Lines

Before starting, clear your previous drawing.

We are going to work on drawing tangent lines from the home screen. First, enter in a
function by pressing the [Y=] button, this screen should appear

Plot 1 Plot 2 Plot 3
Y1=
Y2=
Y3=

Then using your arrows scroll down to Y1= and enter in the given function and press
[GRAPH], this will display the graph.
                                       Y1=x^3

Now you would like to return back to the home screen. In order to draw the tangent line
your must use the Draw menu by pressing [2nd] and then [PRGM]. Then you can scroll
down to 5:Tangent( and press enter or press [5]. This should bring you back to the home
screen. Now you would like to enter in the Y1 function, to do so you press [VARS]. This
display will appear

VARS Y-VARS
1: Window ….
2: Zoom …
3: GDB ….
You want to highlight Y-VARS by using your arrows. After Y-VARS is selected you
should see this display

VARS Y-VARS
1: Function
2: Parametric
3: Polar
4: On/Off …

You should select 1:Function and press enter which will then give you this display.

FUNCTION
1:Y1
2:Y2
3:Y3
4:Y4

You should select 1:Y1 and press enter. This will bring you back to the home screen with
this display.

Tangent ( Y1

Next, you want to enter in a [ , ] and the point at which you would like the tangent to be
drawn. So you should then have a screen like this

Tangent ( Y1, #

At this point you can press enter. The graph screen will appear with the tangent line
drawn to the function.

Moving Functions and Drawing the Inverse

Before starting, clear your previous drawing.

   1. Moving Functions

First we are going to enter a function in the [Y=] menu. To keep it simple we will enter
the listed function into the Y1=
                                           (x-3)^3

Then press graph to view the function. After viewing the function return back to the
home screen. From here we will move the function vertically up and down the graph.
In order to do this, you enter the Draw menu by pressing [2nd] and then [PRGM], where
you then select 6:DrawF. This will bring you back to the home screen with this display

                                          DrawF
Next you want to enter in the Y1 function, in order to do this follow the steps previously
listed in drawing tangent lines involving the [VARS] button.

You should then have a home screen that looks like this

                                         DrawF Y1

At this point you can move your function down by subtracting a number, or move your
function up by adding a number.

i.e.      DrawF Y1+5

The function will then move 5 units up

       2. Drawing the inverse

Before starting, clear your previous drawing.

To draw the inverse of a function we can also use the Draw menu. To save time we will
use the function (x-3)^3 from the previous activity.

First we will return to the home screen where we will then select 8:DrawInv from the
Draw menu by pressing [2nd] and then [PRGM]. You should then return to the home
menu with this display on your screen

                                         DrawInv

Now you can follow the same steps from the previous activity to insert your Y1 function.
Your screen should then display this screen.

                                       DrawInv Y1

You can now press enter and your inverse will appear on your graph screen.


Exercises:

       1. Use the second line segment technique to draw a 4 x 4 square which should
          include all non origin vertices.
       2. Draw a tangent line to the function Y=cos(x) at x=0 and explain what is true
          of this tangent line.
       3. Create a function of your own and shift that function both vertically and
          horizontally a given amount.