Texas Instruments TI-89 Voyage 200, User Manual

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2. Display the Home screen. Then store the
radius, 5, in variable r.
Press
"
5
9
j
R
¸
3. Display and clear the
Y= Editor
. Then
define y1(x) = , the top half of
a circle.
In function graphing, you must define
separate functions for the top and bottom
halves of a circle.
Press
8 # ,
8
¸ ¸ 2 ]
j
R
Z
2
|
X
Z
2
d ¸
4. Define y2(x) = , the function for
the bottom half of the circle.
The bottom half is the negative of the top
half, so you can define y2(x) =
L
y1(x).
Use the full function name
y1(x)
, not
simply y1.
Press
¸ ?
Y 1
c
X
d ¸
Steps and keystrokes Display
5
!
r
r
2
x
2
–
( )
r
2
x
2
– –