Question

Determine if the graph is symmetric about the x-axis, the y-axis, or the origin. r = 2 cos 3θ

Answer 1

testing for y-symmetry let's make r = 5 cos 3θ and set θ=π−θ sor=5cos3θθ=(π−θ)r=5cos(3(π−θ))⟹r=5cos(3π−3θ)

Answer 2

The graph is symmetric around the x-axis as shown in the graph I have provided.