Polar Graphing - Texas Instruments TI-89 Titanium Short User Manual

Polar Graphing

The graph of the polar equation r1(q) = A sin B q forms the shape of a
rose. Graph the rose for A=8 and B=2.5. Then explore the appearance of
the rose for other values of A and B.
Steps and keystrokes
1. Display the
mode, select
select
RADIAN
Press 3 B 3 D D D B 1 ¸
2. Display and clear the
the polar equation r1(q) = A sin Bq.
Enter 8 and 2.5 for A and B, respectively.
@ 8 # , 8 ¸ ¸ 8 2 W 2.5
8 Ï d ¸
3. Select the
ZoomStd
graphs the equation.
• The graph shows only five rose petals.
– In the standard viewing window,
the Window variable qmax = 2p.
The remaining petals have q values
greater than 2p.
• The rose does not appear symmetrical.
Both the x an y axes range from L10
–
to 10. However, this range is spread
over a longer distance along the x
axis than the y axis.
Press „ 6
4. Display the
qmax to 4p.
4p will be evaluated to a number when you
leave the
Window Editor
Press 8 $ D 4 2 T
58
dialog box. For
MODE
. For Angle mode,
POLAR
.
Y= Editor
viewing window, which
Window Editor
.
Graph
. Then define
, and change
Display
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