\alpha

B = Intersect(yAxis, zAxis)
a = OrthogonalLine(B, xOyPlane)
A = Point(a)
M = (2.7485719512122415, 2.064576149456146, 4.440892098500626E-16)
M' = (-2.3390297016939634, 1.638838799112479, 0)
b = Line(M, M')
c = OrthogonalLine(B, b, space)
C = Intersect(c, b)
d = Line(A, C)
α = Angle(A, C, M')
β = Angle(A, B, C)
γ = Angle(M, C, B)