Getting started
Texas Instruments TI-85 and TI-86 calculators
Overview:
Your graphing calculator or computer is a powerful and flexible tool, which you would
probably be able to use fairly well without reading any instructions. It is important, however, to learn
how to take advantage of some of its not-so-obvious features and how to avoid making errors using it.
Study these instructions and be sure you can work the tune-up exercises at the end.
Topics:
•
Basic operations
•
Priority of operations in calculations
•
The dangers of using improper parentheses
•
Exact and approximate decimal values of functions
Basic operations
Press the
ON
key to start the calculator. Press
2nd
followed by the up cursor key
N
to increase
display contrast and by
H
to decrease it. Change the four AAA batteries as soon as the screen dims
when graphs are generated. Press
2nd
MODE
. The screen should show
Normal
Sci Eng
Func
Pol Param DifEq
Float
012345678901
Dec
Bin Oct Hex
Radian
Degree
RectV
CylV SphereV
RectC
PolarC
dxDer1
dxNDer
The words printed in bold type here should be highlighted on the screen. If another item is highlighted or
you want to change a selection, use the cursor keys to move the flashing box to the correct item and press
ENTER
.
<
Normal
>
denotes normal notation for decimals;
<
Sci
>
is for scientific notation; and
<
Eng
>
for engineering notation. With
<
Float
>
selected decimals are printed with twelve digits. Choosing an
integer instead of
<
Float
>
causes that many digits be shown after decimal points. (Use the second 0
for ten digits and the second 1 for eleven digits.)
<
Radian
>
is for radians and
<
Degree
>
for degrees.
<
Func
>
is selected to generate graphs
y
=
f
(
x
) of functions.
<
Pol
>
is for polar coordinates,
<
Par
>
is
used with parametric equations, and
<
DifEq
>
is for differential equations. The other selections will be
explained as needed.
Press
EXIT
or
2nd
QUIT
to return to the home screen and then
GRAPH
for the first row of the
graph menu. Press
MORE
to see the second row of the menu and then press
F3
for
<
FORMT
>
. The
screen should read
RectGC
PolarGC
GridOff
GridOn
CoordOn
CoordOff
AxesOn
AxesOff
DrawLine
DrawDot
LabelOff
LabelOn
SeqG
SimulG
with the words in bold highlighted. With
<
RecGC
>
and
<
CoordOn
>
selected, rectangular coordinates
are used and the coordinates of the cursor are displayed with graphs. Points on graphs are connected
if
<
DrawLine
>
is chosen and not with
<
DrawDot
>
. Use
<
SeqG
>
(sequential graphs) to have two
or more graphs drawn one after the other, and
<
SimulG
>
(simultaneous graphs) to have them drawn
at the same time. If
<
GridOn
>
were selected, dots would be placed on the screen at the points whose
coordinates correspond to the tickmarks on the axes. The axes would not be shown with
<
AxesOff
>
and labels would be displayed with
<
LabelOn
>
.
The key
2nd
activates the yellow commands above the keys.
EXIT
is used to return to a previous
screen and to remove menus.
2nd
QUIT
returns you to the home screen where calculations are made.
CLEAR
with the cursor on a blank line of the home screen clears the screen. In other cases it clears the
line with the cursor or removes a menu.
The key
ALPHA
puts the calculator in upper-case alpha mode, activating the blue letters and
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