Góc BOC = ?

O = (120.83801103039498, 176.6519489862473)
B = (226.27263332468067, 177.3548464682092)
a = Segment(O, B)
A = (185.96146273416545, 242.45018227270114)
b = Segment(O, A)
C = (138.86733144271784, 258.9682730988059)
c = Segment(O, C)
α = Angle(B, O, A)
β = Angle(A, O, C)