ω = Circle((0, 0), 1)
A = PointIn(Circle[(0, 0), 1])
B = PointIn(Circle[(0, 0), 1])
A' = Mirror(A, Circle[(0, 0), 1])
B' = Mirror(B, Circle[(0, 0), 1])
Oblúk = If(Length[A] ≟ 1, Circle[A, B, B'], Circle[A, B, A'])