O_1 = (-1, 2)
O_2 = (4, 2)
c = Circle(O_1, 1)
d = Circle(O_2, 1)
t = 0 (slider from 0 to 1, step 0.01)
α_1: ((2 * π) * t)
α_2: π + ((4 * π) * t)
M_1: O_1 + (1; (90 + (α_1 * 180 / π))°)
M_2: O_2 + (1; (90 + (α_2 * 180 / π))°)
a = Segment(M_1, M_2)
b = Segment(O_1, M_1)
e = Segment(O_2, M_2)
M_10 = (-1, 3)
α = Angle(M_10, O_1, M_1)
M_20 = (4, 1)
β = Angle(M_20, O_2, M_2)
f = Segment(O_1, M_10)
g = Segment(O_2, M_20)