Chapter 3: Function Graphing
69
3. Press
ƒ a
to display the
YVAR
shortcut menu, move the cursor to the function name,
and then press
Í
.
"
expression
"
!
Y
n
When the instruction is executed, the TI-84 Plus stores the expression to the designated variable
Y
n
, selects the function, and displays the message
Done
.
Evaluating Y= Functions in Expressions
You can calculate the value of a Y= function
Y
n
at a specified
value
of X. A list of
values
returns a list.
Y
n
(
value
)
Y
n
({
value1,value2,value3, . . .,value n
})
Selecting and Deselecting Functions
Selecting and Deselecting a Function
You can select and deselect (turn on and turn off) a function in the Y= editor. A function is selected
when the
=
sign is highlighted. The TI-84 Plus graphs only the selected functions. You can select
any or all functions Y1 through Y9, and Y0.
To select or deselect a function in the Y= editor, follow these steps.
1. Press
o
to display the Y= editor.
2. Move the cursor to the function you want to select or deselect.
3. Press
|
to place the cursor on the function’s
=
sign.
4. Press
Í
to change the selection status.
When you enter or edit a function, it is selected automatically. When you clear a function, it is
deselected.
