a = 3 (slider from 3 to 8, step 1)
θ = 0 rad (slider from 0 to 360°, step 1°)
f(θ) = (2 * cos((a * θ)))
r_1: f(θ)
O: (0, 0)
A: ((r_1 * cos(θ)), (r_1 * sin(θ)))
g = Segment(O, A)
P: (θ, f(θ))
h = Segment((θ, 0), P)
P_x: (θ, 0)
Rose = CurveCartesian(((2 * cos((a * θ))); θ), θ, 0, (2 * π))