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O = (-0.64, 1.76)
B = (2.36, 1.76)
a = Ray(O, B)
C = (2.02, -0.62)
A = (1.24, 0.38)
D = (1.7, 1.54)
c = CircleArc(O, A, D)
F = (3.48, 1.02)
G = (3.08, 0.36)
H = (2.64, -0.36)
E = Point(c)
u = Vector(E, A)
α = 0.7853981633974483 rad (slider from 0 to 6.283185307179586, step 0.017453292519943295)
I = Point(a)
I' = Rotate(I, -α, O)
β = Angle(I', O, I)
b = Ray(O, I')