P (sin(α) / cos(α))

Bogenmaß α

Gradmaß α

A = Intersect(xAxis, yAxis)
c = Circle(A, 1.0)
D = (1.2494095469411552, 0.8386578104775413)
B = Intersect(xAxis, yAxis)
C = Point(c)
E = Point(c)
d = CircleArc(B, C, E)
α = Angle(C, B, E)
u = Vector(B, E)