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

1. Sep 7, 2013

### PsychonautQQ

1. The problem statement, all variables and given/known data
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?

2. Sep 7, 2013

### Zondrina

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 $\theta = 2\pi$.