ε

P_3'

P_3

P_2'

P_2

P_1'

P_1

Leitgerade l

a: Abstand zur Wand / Leitgerade

“Streckfaktor” ε (num. Exzentrizität) 

a

a

a

a

Abstände d(P,F) und d(P,l)

Abstand d(f,l)

Parabel

Ellipse

Hyperbel

Spuren löschen

\overline{PF}= 1·a

Leitgeradenkonstruktionen

Kreise einblenden

IMP10

t = 3 (slider from 3 to 12, step 3)
L: (0, 12)
K: (0, 1)
s = Segment(K, L)
r = 0.5 (slider from 0 to 1, step 0.1)
a = 7 (slider from 0 to 13, step 0.5)
F: (0, t)
k_1 = Circle(F, (1 / r * a))
A: (0, a)
f = Line(A, y = 0)
B, C = Intersect(k_1, f)
k_3 = Circle(F, (r * a))
k_2 = Circle(F, a)
D, G = Intersect(k_2, f)
E, H = Intersect(k_3, f)
Leitgerade: y = 0
g = Segment(F, H)
h = Segment(F, G)
i = Segment(F, C)
I = Point(Leitgerade)
j = OrthogonalLine(I, Leitgerade)
J = Intersect(j, f)
k = Segment(I, J)
L_2: (x(G), 0)
L_1: (x(H), 0)
L_3: (x(C), 0)
l = Segment(H, L_1)
m = Segment(G, L_2)
n = Segment(C, L_3)
b = true
c = true
d = true
e = true
o = true
p: 1 / r
Text3: "\overline{PF} = " + (LaTeX[r]) + "·a"
Text5: "\overline{PF}=" + (LaTeX[p]) + "·a"
q = false