Chiều quay dương

Chiều quay âm

α = 1.064650843716541 rad (slider from 0 to 6.283185307179586, step 0.017453292519943295)
A = (-2.8486656736488403, 5.735671185726327)
B = (4.588982531945389, 5.703333584832438)
a = Segment(A, B)
B' = Rotate(B, α, A)
b = Segment(A, B')
c = CircleArc(A, B, B')
C = (13.546497979552376, 5.670995983938551)
D = (21.04882138693443, 5.638658383044661)
d = Segment(C, D)
D' = Rotate(D, -(α), C)
e = Segment(C, D')
f = CircleArc(C, D', D)
β = Angle(B, A, B')
γ = Angle(D', C, D)