cosα

i sin α

O = Point(xAxis)
c = Circle(O, 1.0)
A = Point(c)
B = Intersect(c, xAxis, 2.0)
u = Vector(O, A)
α = Angle(B, O, A)
Z = (0.6577777777777778, 2.0155555555555558)
v = Vector(O, Z)
a = Line(A, yAxis)
b = Line(A, xAxis)
C = Intersect(b, yAxis)
A' = Intersect(a, xAxis)
d = Segment(A', A)
e = Segment(C, A)
f = Line(O, Z)
g = Line(B, Z)
h = Line(A', g)
Z' = Intersect(h, f)
w = Vector(O, Z')
W = Rotate(Z, 90.0°, O)
z = Vector(O, W)
i = Line(O, W)
E = Intersect(c, yAxis, 1.0)
j = Line(W, E)
k = Line(C, j)
W' = Intersect(i, k)
l = Vector(O, W')
m = Line(W', v)
n = Line(Z', z)
P = Intersect(n, m)
p = Vector(O, P)
q = Segment(W', P)
r = Segment(P, Z')
β = Angle(Z', O, P)