\"\"

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(a)

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The polar equation is \"\".

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Since polar equation is a cosine function, it is symmetric with respect to the polar axis.

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Construct a table and calculate the values of \"\" on \"\".

\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \
\"\"\"\"\"\"\"\"\"\"\"\"
\"\"\"\"\"\"\"\"\"\"\"\"
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Graph :

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1. Draw a polar coordinate plane.

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2. Use the points and polar axis symmetry to sketch the curve.

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\"\"

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\"\"

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(b)

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The rectangular coordinates are \"\".

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Find polar coordinates \"\".

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Find \"\":

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\"\".

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Substitute \"\" in the above equation.

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\"\"

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Find \"\" :

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\"\"

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Since \"\", the angle is \"\".

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Substitute \"\" in the above equation.

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\"\"

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The sound originates from the point with polar coordinates \"\" .

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From the graph, this point does not lie within the polar region.

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Hence the microphone will not detect the sound.

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\"\"

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(a)

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Graph of the polar equation \"\" is

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\"\"

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(b) 

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The sound originates from the point with polar coordinates \"\".

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The microphone will not detect the sound.