Determine if the graph is symmetric about the x-axis, the y-axis, or the origin

r = 4 cos 5θ

Question

Determine if the graph is symmetric about the x-axis, the y-axis, or the origin

r = 4 cos 5θ

jdoe0001 · Answer

in short.... the check for symmetry for the y-axis, x-axis or the pole or y=x line

$\large 
\begin{array}{rlll}
&replace\quad (\theta,r)
\\hline\
\frac{\pi}{2}line \ (y)&(-\theta,-r)\
polar-axis\ (x)&(r,-\theta)\
pole\ line\ (y=x)&(-r,\theta)
\end{array}
$

if they yield an equivalent equation, after simplification, they it has symmetry at that line

anonymous · Answer

Thanks I got it! (: I figured it out a little before you replied. But thanks for helping me out! (: