R = 1
I = (1.844935602466029, -0.34437857951934403)
k = Circle(I, R)
A = (-2.862828500053068, 0.8432486177332028)
I' = Point(k)
A' = (8.734841472577006, -4.487280240420735)
a = Segment(A, I)
b = Segment(I, A')
c = Segment(A, I')
d = Segment(I', I)
e = Segment(I', A')
f = OrthogonalLine(I, d)
n = 1.5
g = Circle(A, 1)
B = Intersect(g, a)
u = Vector(A, B)
h = Circle(I, 1)
C = Intersect(h, b)
v = Vector(I, C)
d1: Distance[A, I] + n * Distance[I, A']
d2: Distance[A, I'] + n * Distance[I', A']
texte1: "chemin  1 = " + d1 + "
chemin  2 = " + d2 + "
L2 - L1 = " + (d2 - d1)
D = Point(f)
E = Point(f)
α = Angle(D, I, A)
β = Angle(E, I, A')
texte2: "sin(α) = " + (sin(α)) + "
n.sin(β) = " + (n * sin(β)) + "
 " + "
donc : sin(α) = n.sin(β)  "