Ex 148. Et pourtant, elle tourne! c)
Author: Frédéric Chanez

Point P

A = (-2.7830812632531785, 4.428058941173656)
B = (10.910494189003511, 3.116498954675044)
a = Line(A, B)
C = (-1.62, 0.52)
b = Line(C, a)
c = OrthogonalLine(B, a)
D = Intersect(b, c)
d = LineBisector(B, D)
O = Point(d)
e = Segment(A, B)
α = 3.141592653589793 rad (slider from 0 to 6.283185307179586, step 0.017453292519943295)
A' = Rotate(A, α, O)
B' = Rotate(B, α, O)
e' = Segment(A', B')
P = Point(a)
P' = Rotate(P, α, O)
h = CircleArc(O, P, P')
f = Segment(P, O)
g = Segment(O, P')
β = Angle(P, O, P')
i = true