AP Precalculus / Unit 3: Trigonometric and Polar Functions

3.14 Polar Function Graphs

3 practice questions

Notes

Graph $r=f(\theta)$ by plotting $r$ at each angle.

$r=a$: circle. $r=a\cos\theta$: circle through the origin.
$r=a\sin(n\theta)$: rose with $n$ petals ($n$ odd) or $2n$ petals ($n$ even).
$r=a+b\cos\theta$: limaçon (cardioid if $a=b$).

Practice

$r=3\sin(2\theta)$ has how many petals?

$r=2+2\cos\theta$ is a:

$r=5$ is a:

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