Texas Instruments TI-73 Explorer Quick start guide

10/8/2002 © 2002 Texas Instruments
TI-73 / TI 83 Plus
Guess My Coefficients
Getting Started
Starting and Quitting the Application
How To…
Use On-Screen Options and Menus
Change Game Options
Select a Game
Enter Coefficients and Constants
Use Hints
More Information
Getting Help
Error Recovery
TI

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Important Information
Texas Instruments makes no warranty, either expressed or
implied, including but not limited to any implied warranties of
merchantability and fitness for a particular purpose, regarding
any programs or book materials and makes such materials
available solely on an "as-is" basis.
In no event shall Texas Instruments be liable to anyone for
special, collateral, incidental, or consequential damages in
connection with or arising out of the purchase or use of these
materials, and the sole and exclusive liability of Texas
Instruments, regardless of the form of action, shall not exceed
any applicable purchase price of this item or material. Moreover,
Texas Instruments shall not be liable for any claim of any kind
whatsoever against the use of these materials by any other
party.
Graphing product applications (Apps) are licensed. See the
terms of the license agreement for this product.
Microsoft, Windows, Windows NT, Apple, and Macintosh are trademarks of their
respective owners.

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What Is the Guess My Coefficients
Application?
The Guess My Coefficients application familiarizes you with
various forms of linear, quadratic, and absolute value functions.
You determine the coefficients and constants (value such as
roots and intercepts) for a function by viewing the graph of the
function. If you need help, a HINT option shows points on the
graph and lets you trace the graph.
The Guess My Coefficients application is a concept application
that TI wants to share with our customers, educators, and
students before the product definition and testing are complete. It
is an alpha software version, and as such, it may contain
imperfections, or the coding may be incomplete.
TI invites your feedback concerning the functionality and
educational value of the Guess My Coefficients application.
Please send your comments and questions to
[e-mail].

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What You Need
Note In this guidebook, any information that pertains to the TI-83 Plus also
pertains to the TI-83 Plus Silver Edition, unless otherwise noted.
Hardware and Software Note
TI-73 with version 1.60 or latest version
of the Graph Explorer software
—or—
TI-83 Plus or TI-83 Plus Silver Edition
with version 1.15 or latest version of
the operating system (OS) software
You can download a free copy of
the latest Graph Explorer or
operating system software from
education.ti.com/softwareupdates.
Follow the link to Operating
Systems.
Computer with Microsoft ® Windows®
95/98/2000, Windows NT®, or Apple®
MacIntosh® OS 7.1 or higher installed
TI-GRAPH LINK™ computer-to-device
cable If you do not have this cable, call your distributor or order the cable
from the TI on-line store.
TI Connect™ software, which works
with most supported models of Flash-
based TI graphing devices.
—or—
TI-GRAPH LINK software that is
compatible with the TI-73 or the
TI-83 Plus
You can download free copies of
TI Connect and TI-GRAPH LINK
software from
education.ti.com/softwareupdates.
Follow the link to Connectivity
Software.

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Where to Find Installation Instructions
Detailed instructions on installing this and other applications are
available at education.ti.com/guides. Follow the link to Flash
Installation Instructions.
Getting Help
The instructions in this guidebook are only for this application. If
you need help using the TI-73 or TI-83 Plus, refer to its
comprehensive guidebook at education.ti.com/guides.
For this application, help is available for each game from the
SELECT A GAME and OPTIONS screens, and from each SELECT A
FUNCTION screen.
1. Select HELP to display the HELP screen.
2. Press }and †to scroll through the help text.
3. Select BACK to leave the HELP screen and return to the
previous screen.

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Starting and uitting the Application
Starting the Application
1. Press Œto display the list of applications on your TI-73 or
TI-83 Plus.
2. Select GuesCoef. The application’s information screen is
displayed.
3. Press any key to continue. The programmer’s screen is
displayed.
4. Press any key to continue. The SELECT A GAME menu is
displayed.
Quitting the Application
From the SELECT A GAME screen, select QUIT (press o) or press
y 5.

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Navigating within the Application
Selecting Menu Items
You can select menu items in the following ways:
•Press }or †to highlight the menu item, and then press
Íto select it.
•Press the number key that corresponds to the menu item.
Using On-Screen Options
Each screen displays one or more options along the bottom of
the screen. To select an option, press the graphing key directly
below the option.
o
p
q
r
s
For example,
press sto
select HELP.

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Setting Game Options
You can set three different options for the games. The options
that you select apply to every function type (game) on the
SELECT A GAME screen.
Option Description
Fixed Number
of Problems The game consists of the defined number of problems displayed on the right side of the screen, no matter how many
incorrect answers you give. When this option is not selected,
you play the game until you have given three incorrect
answers.
Give One
Retry You have two chances per problem to input the correct answer.
Show Grid Displays the grid with the graph of the function.
1. From the SELECT A GAME screen, select OPTIONS to display
the GAME OPTIONS screen.
2. Press }or †to highlight an option.
Number of problems box

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3. Select Ÿor press Íto toggle the checkboxes.
4. Select BACK to confirm your changes and return to the
SELECT A GAME screen.
Changing the Number of Problems
1. On the GAME OPTIONS scree, press }or †to highlight the
number of problems box and then press Í.
2. Enter the number of problems (1-99) and then press Í.
Tip If you make a mistake when you enter the number of problems,
you can correct this in one of the following ways:
•Press ‘to delete the entire number.
•Press |to delete the last digit of the number.
Press Íto confirm your changes or y5to discard.
3. Select BACK to confirm your changes and return to the
SELECT A GAME screen.

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Selecting a Game
1. Select the function type to play from the SELECT A GAME
screen.
2. Select a function form from the SELECT A FUNCTION screen to
start the game.
The following function forms are available:
Function Type Form
Linear y = mx + b
ax + by = c
Quadratic y = a·x² + k
y = a·(x – h)² + k
y = a·(x – r)(x – s)
Absolute Value y = a·|x| + k
y = a·|x – h| + k
Tip You can also play the game with multiple function types instead of
just one type. From the SELECT A GAME screen, select ALL or
LINEAR & QUADRATIC or from the function-specific screens, select
BOTH / ALL FORMS.

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Entering Coefficients and Constants
Keep the following hints in mind when you enter values.
•The values that you input are always integers.
•For the y = a·(x – r)(x – s) form, the coefficient ais either
M1 or 1.
•All multiples of the correct solution for ax + by = c are
accepted.
•All problems appear in the window xmin = L9, xmax = 9,
ymin = L6, ymax = 6.
•For quadratic and absolute value functions, ais from the set
± {1,2,3,4}.
1. Select a game. Your score and the number of the current
problem are displayed along with the graph of a function.

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2. Press any key to study the graph.
3. Press any key to display the input dialog box.
4. Press }or †to select a coefficient, and then input the
value.
5. Repeat step 4 for the remaining value(s), and then press
Íto check your answer.
Tip If you make a mistake when you enter a coefficient, you can
correct this in one of the following ways:
•Press ‘to delete the entire number.
•Press |to delete the last digit of the number.
•Press Ìto leave the digits unchanged and toggle the sign.
Function type
Coefficients or
constants
you input

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A graph of the function with the values you input is displayed
along with the graph of the function in the problem. A message
displays stating whether your answer is correct or incorrect.
•If your answer is correct, select OK to proceed to the next
problem.
•If your answer is incorrect and your game options allow one
retry, a message appears telling you to try again.
-Select GRAPH (r) to show your guess and the
problem, and then press Íto display the input dialog
box.
—or—
Select OK to go directly to the input dialog box.
-Repeat steps 4 and 5 to change your input and check your
new answer.
Tip For all function types except ax + by = c, a check mark appears
next to a correct value in the input dialog box.
•If your final answer is incorrect, select OK to display the
correct answer.

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Using Hints
If you are not sure about the values of a graph, you can obtain a
hint, which marks some points on the graph and lets you trace
the graph.
1. Select HINT.
2. Press |or ~to trace the graph and display the (x, y)
coordinates of the points given in the hint.
Function Type Points Given in Hints
y = mx + b The y-intercept (0, b); one other point on the
graph
ax + by = c Intersections with the axes (c/a, 0 ) and (0, c/b)
y = a·x² + k The vertex (0, k); one other point on the graph
at x = 1
y = a·(x – h)² + k The vertex (h, k); one other point on the graph
at x = h + 1
The hint shows
the x-intercepts
for this function.

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Function Type Points Given in Hints
y = a·(x – r)(x – s) The two roots (r, 0) and (s, 0)
y = a·|x| + k The vertex (0, k); one other point at x = 1
y = a·|x – h| + k The vertex (h, k); one other point at x = h + 1
3. Press any key to return to the input dialog box.

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Scoring
Your score is computed based on whether you input the correct
answer on the first or second try and whether you used a hint to
help you determine the correct answer.
Correct Answer
Hint First Try Second Try
Incorrect
Answer
Not used 4 2 M2
Used 3 1 M2

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Entering Initials in the High Score Table
When you reach a high score, you can enter your initials in the
high score table. The initials displayed are AAA until you change
them.
1. Press }and †to cycle the display through the available
letters, in alphabetical order.
2. Press |and ~to move the cursor between the positions for
each letter.
3. Press Íor select OK from the on-screen options to
confirm your input.
Your initials and your points are added to the high score list.

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Deleting the Application
TI-7
1. Quit the App.
2. Press y L to display the MEMORY menu.
3. Select Delete.
4. Select Apps.
5. Move the cursor to GuesCoef.
6. Press Í. A confirmation message is displayed.
7. Select Yes to delete the application.
TI-8 Plus
1. Quit the App.
2. Press y L to display the MEMORY menu.
3. Select Mem Mgmt/Del.
4. Select Apps.
5. Move the cursor to GuesCoef.
6. Press {. A confirmation message is displayed.
7. Select Yes to delete the application.

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Installation Error Messages
Low Battery
Do not attempt to download a Flash application if the low-battery
message appears on the home screen. Low battery indication is
shown on the initial screen. If you receive this error during an
installation, change the batteries before trying again.
Invalid Signature or Certificate
This application does not need a certificate to run. If this error
occurs, it is probably due to a link failure caused by electrical
interference. Try to install the application again.
Error in Xmit
This problem is usually associated with the unit-to-unit cable and
its connection between the devices. Make sure the cable is firmly
inserted in the link port of each device.

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Communication Error
This error indicates that the TI Connect™ software (“Unable to
communicate with device”) or TI-GRAPH LINK™ software (“Link
Transmission Error”) is unable to communicate with the device.
The problem is usually associated with the TI-GRAPH LINK
cable and its connection to the device or to the computer.
•Make sure the cable is firmly inserted into both the device link
port and the computer.
•Verify that the correct cable type is selected in the software
link settings.
•Verify that the correct communications port (Com Port) is
selected in the software link settings. (This does not apply if
using the USB port and TI Connect software.)