# Lesson goal: Sin, cos and circles

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Polar plots are fun because interesting curves can be created that would be much harder in $xy$-coordinates. Polar plots are defined by two variables, $r$ and $\theta$. Here, $r$ is the distance from the origin $(0,0)$ and $\theta$ is the angle from the $+x$-axis. We'll make some interesting polar plots here.

# Now you try. Try fixing the r= statement.

This code will not run. You have to put in some function for the r= line. Try these
• $r=1+cos(\theta)$
• $r=5cos(5\theta)$
• $r=sin(\theta)cos(\theta)$
• $r=sin(\frac{10\theta}{7})$
• $r=sin(\frac{5\theta}{3})$
• $r=sin(\frac{\theta}{3})$
• $r=2e^{0.001\theta}$ (this one might take a few seconds to finish).
Note that $\theta$ is theta here and if you plot is too small or large, try changing the value of the variable zoom Dismiss.
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