HP 39g+ - Manual (Page 60)

2-20 Aplets and their views
Example: plotting a circle
Plot the circle, x
2
+ y
2
= 9. First rearrange it to read
.
To plot both the positive and negative y values, you need to
define two equations as follows:
and
1. In the Function aplet, specify the functions.
>$3/(7@ Select
Function TU6SU•
>6+,)7@ √ > @ 9
>@>;75@>;@> @>(17(5@
>  @ >6+,)7@ √ > @ 9
>@>;75@
>;@> @>(17(5@
2. Reset the graph setup to the default settings.
>6+,)7@
SETUP - PLOT
>6+,)7@
CLEAR
3. Plot the two functions
and hide the menu so that
you can see all the circle.
>3/27@
H@IV•ÃH@IV•
4. Reset the numeric setup to the default settings.
>6+,)7@
SETUP - NUM
>6+,)7@
CLEAR
5. Display the functions in numeric form.
>180@
y 9 x
2
–
±
=
y 9 x
2
– = y 9 x
2
– – =