Final answer:
The parametric equations are x = -3sin(θ/2) and y = -3cos(θ/2). Four unique points on the parametric curve are (0, -3, 0), (-3/√2, -3/√2, π/2), (0, -3, π), and (3/√2, -3/√2, 3π/2).
Step-by-step explanation:
The parametric equations given are:
x = -3sin(θ/2)
y = -3cos(θ/2)
To find four unique points on the parametric curve, we can substitute different values of θ into the equations. Let's choose θ = 0, π/2, π, and 3π/2:
For θ = 0:
x = -3sin(0/2) = 0
y = -3cos(0/2) = -3
The point is (0, -3, 0).
For θ = π/2:
x = -3sin(π/4) = -3/√2
y = -3cos(π/4) = -3/√2
The point is (-3/√2, -3/√2, π/2).
For θ = π:
x = -3sin(π) = 0
y = -3cos(π) = -3
The point is (0, -3, π).
For θ = 3π/2:
x = -3sin(3π/4) = 3/√2
y = -3cos(3π/4) = -3/√2
The point is (3/√2, -3/√2, 3π/2).