(a)
\The polar equation is
.
Since polar equation is a cosine function, it is symmetric with respect to the polar axis.
\Construct a table and calculate the values of
on
.
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Graph :
\1. Draw a polar coordinate plane.
\2. Use the points and polar axis symmetry to sketch the curve.
\.gif\")
(b)
\The rectangular coordinates are
.
Find polar coordinates
.
Find
:
.
Substitute
in the above equation.

Find
:

Since
, the angle is
.
Substitute
in the above equation.

The sound originates from the point with polar coordinates
.
From the graph, this point does not lie within the polar region.
\Hence the microphone will not detect the sound.
\(a)
\Graph of the polar equation
is
.gif\")
(b)
\The sound originates from the point with polar coordinates
.
The microphone will not detect the sound.