Polar Coordinates
A. Converting
Polar to Rectangular Coordinates
B. Converting
Rectangular to Polar Coordinates
C. Polar Graphing
A. Converting Polar to Rectangular Coordinates
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We will convert the
point |
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written in
polar coordinates to rectangular coordinates. Put your
calculator in Radian mode. Then enter the point in polar coordinates with the
conversion as shown on the home screen. The angle symbol is above the comma
key and the conversion command is under the CPLX menu. Press the right arrow
key to see more digits of the y coordinate. Thus, the point in
rectangular coordinates is
.
B. Converting Rectangular to Polar Coordinates
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We will convert the point |
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written in
rectangular coordinates to polar coordinates. Put your
calculator in radian mode, and execute the conversion command as shown on the
home screen. The conversion command is under the CPLX menu. Press the right
arrow key to see more digits of the θ coordinate.
Thus, the point in polar coordinates is
.
C. Polar Graphing
We will graph the 4-petaled rose
 . Put your
calculator in radian mode and in polar graphing mode by selecting MODE\Pol.
Press GRAPH\r(θ)= to see the polar function screen. The calculator expects
each r to be a function of θ. The θ symbol can be obtained by
pressing the F1 key. |
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The WINDOW screen is similar to the one for
parametric graphing: In addition to an x and y range, you must
specify a θ range that the calculator will use to plot polar points. For
this example of graphing , use the range 
with a θ step of
. Do zoom fit followed by zoom square to obtain
the last graph.
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Exercise: Trace the graph in the above example. In what order are the leaves of the rose traced?
Exercise: Try a θ step of .001, and then try a θ step of .5. Explain what happens.