Μεγάλος Άξονας = AB
Μικρός Άξονας = CD

a = 2 (slider from 0 to 5, step 0.1)
b = 1 (slider from 0 to 5, step 0.1)
c: x^(2.0) / a^(2.0) + y^(2.0) / b^(2.0) = 1.0
A, B = Intersect(c, xAxis)
C, D = Intersect(c, yAxis)
d = Segment(A, B)
e = Segment(D, C)
O = Intersect(e, d)
f = Tangent(D, c)
g = Tangent(A, c)
h = Tangent(B, c)
i = Tangent(C, c)
j = Line(C, D)
k = Line(B, A)
E_1: (-sqrt(a^(2.0) - b^(2.0)), 0.0)
E1 = 0
E2: -(E1)
E_2: -(E_1)