α = 0.7853981633974483 rad (slider from 0 to 6.283185307179586, step 0.017453292519943295)
D = (1, 0)
A = Intersect(xAxis, yAxis)
O = Intersect(xAxis, yAxis)
k = Circle(O, 1)
C = Rotate(D, α, A)
B: (x(C), 0)
f = Ray(A, D)
d1, c, a, b = Polygon(A, B, C)
g = Ray(A, C)
α_1 = Angle(D, A, C)
alpha_{bogen} = Arc(k, D, C)
alpha_{bogenAngepasst} = If(α ≟ 360°, (2 * π), alpha_{bogen} ≟ π / 2, π / 2, If[alpha_{bogen} ≟ (3 / 2 * π), (3 / 2 * π), alpha_{bogen}])
Text1: "\alpha = " + (LaTeX[alpha_{bogenAngepasst}]) + ""