Graphing r = 1 - cos(theta) (polar coordinates

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Okay the graph SHOULD look like this.
http://jwilson.coe.uga.edu/EMAT6680Fa11/Chun/11/21.png
I can't make sense of this at all. It looks so weird. Why does it bend around the y-axis in such an asymmetric way? I just graphed r = sin(θ) with ease by making a table of r vs θ
and graphing it... but this doesn't seem to be as easy?
 
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A plot of the problem for ##\theta \in [0, 2\pi]## : http://gyazo.com/6811fa8ed2ba867fb9f16d49c3feea09

Notice for ##\theta = 0##, ##cos(\theta) = 1## so that ##r = 0##.

Now, as you increase ##\theta##, notice that ##cos(\theta)## will decrease until ##\theta = \pi## and ##r## will increase.

Then, ##cos(\theta)## begins to increase again and ##r## will start decreasing until ##\theta = 2\pi##.
 
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