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Active Calculus - Multivariable

Activity 9.8.3.
This activity gives you an opportunity to graph some equations in polar coordinates where \(r\) is expressed as a function of \(\theta\text{.}\)
(a)
The following activity will take you through how to create a graph of an equation in \(r\) and \(\theta\text{.}\)
(i)
Draw a graph of \(y=\cos(x)\) for at least \(0 \leq x \leq 2 \pi\text{.}\)
(ii)
Consider the polar equation \(r=\cos(\theta)\text{.}\) Complete the table below by computing the value of \(r\) for each value of \(\theta\) for this equation.
\(\theta\) \(0\) \(\displaystyle\frac{\pi}{4}\) \(\displaystyle\frac{\pi}{6}\) \(\displaystyle\frac{\pi}{3}\) \(\displaystyle\frac{\pi}{2}\) \(\displaystyle\frac{3\pi}{4}\) \(\pi\) \(\displaystyle\frac{5\pi}{4}\) \(\displaystyle\frac{3\pi}{2}\) \(\displaystyle\frac{7\pi}{4}\) \(2\pi\)
\(r\) \(\phantom{\displaystyle\frac{\sqrt{2}}{2}}\)
(iii)
Plot each of the eleven points you found in the previous part on the polar plane and connect them to make a plot of the graph of \(r=\cos(\theta)\text{.}\)
(b)
Graph the equation \(r=1+\cos(\theta)\) in the polar plane.
(c)
Graph the equation \(r=1-\cos(\theta)\) in the polar plane.
(d)
What are the points of intersections for the graphs of \(r=1+\cos(\theta)\) and \(r=1-\cos(\theta)\)