Aufgabe 1
Author: G. Kremb

k = 2 (slider from 0 to 5, step 0.1)
f_k(x) = (x^(3) - 6 k x^(2) + 9 k^(2) x) / 4
t_k(x) = -3 / 4 k^(2) x + 2 k^(3)
A: (2 k, f_k(2 k))