O = (8.236550129167178, -1.1363887317013166)
B_1 = (11.385378275310622, -4.31061065321688)
c = Circle(O, B_1)
A = Point(c)
a = Line(A, O)
B = Intersect(c, a, 2.0)
d = Segment(A, B)
e = CircleArc(O, A, B)
C_1 = Intersect(c, e, 1.0)
D_1 = Intersect(c, e, 1.0)
E = Intersect(c, e, 1.0)
C = Point(e)
b = OrthogonalLine(C, d)
D = Intersect(c, b, 2.0)
I = Intersect(b, d)
α = Angle(D, I, A)
f = Segment(C, D)