Question #75f31

1 Answer
Dec 19, 2017

96 pi

Explanation:

The graph of the polar curve would be as shown below:
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The area enclosed by the curve would be twice the area enclosed by the curve lying over x-axis. The formula for the area enccloseed by a polar curve is given by the formula int_alpha^beta 1/2 r^2 d theta .
In the present case alpha =0 which comes by solving r=16=8(1+ cos theta) and beta =pi , which is obtained by solving r=0=8(1+ cos theta)

Accordingly, the desired area would be 2int_0^pi 1/2 r^2 d theta

=int_0^pi 64(1+cos theta)^2 d theta

=64int_0^pi (1 +2 cos theta + cos^2 theta) d theta

=64int_0^pi (1+2 cos theta +1/2 (1 +cos 2theta)d theta

=64[3/2 theta + 2sin theta +1/4 sin 2theta]_0^pi

=96pi