Gegenvektor
Author: Markus Hohenwarter

a = (1, 2)
a_0 = UnitVector(a)
A = (3, 1)
s = 4 (slider from 1 to 6, step 1)
b: s a_0
B: A + b
T1: "a =  " + a
T2: "a_0 = " + a_0