O = Intersect(xAxis, yAxis)
c = Circle(O, 1)
A = (1, 0)
α = 0.7853981633974483 rad (slider from 0 to 360*°, step 5*°)
A' = Rotate(A, α, O)
OA = Segment(O, A')
d = CircleArc(O, A, A')
OACosinusα: x = cos(α)
Angle = Angle(A, O, A')
OAsinusα: y = sin(α)
DroiteDeTangente = Tangent(A, c)
ProjectionSurAxeTangente = Line(O, A')
Tangente = Intersect(ProjectionSurAxeTangente, DroiteDeTangente)
a = Line(O, A)
CosinusOA = Intersect(OACosinusα, a)
SinusOA = Intersect(OAsinusα, g)
B = Point(d)
b = Segment(O, B)
f = Segment(O, A')
C = Point(c)
e = Segment(C, O)
D = Point(d)
β = Angle(D, O, B)
γ = Angle(D, O, C)