A = Intersect(xAxis, yAxis)
c = Circle(A, 1)
B = Point(c)
a = Segment(A, B)
C = Intersect(c, xAxis, 2)
d = CircleArc(A, C, B)
D = Point(Circle[A, d])
b = Segment(A, D)
α = Angle(xAxis, a)
e = OrthogonalLine(B, yAxis)
f = OrthogonalLine(D, e)
E = Intersect(e, f)
F = Intersect(e, yAxis)
u = Vector(B, F)