n = 382 (slider from 2 to 2000, step 1)
L1_1 = 0
Text1 = Text("Neuberechnung mit F9", (1, -3))
dx: 1 / n
L1 = Append(0, Sequence[RandomNormal[0, sqrt(dx)], k, 1, n])
L2 = Sequence(Sum[L1, k], k, 1, Length[L1])
S = Sequence(Segment[(dx * (i - 1), Element[L2, i]), (dx * i, Element[L2, i + 1])], i, 1, n)
f = If(0 ≤ x ≤ 1, 2 * sqrt(x))
V = Sequence((Element[L2, i] - Element[L2, i + 1])^(2), i, 1, n)
quadratischeVariation = Sum(V)
Text2 = LaTeX(quadratischeVariation, true, true)
f2 = If(0 ≤ x ≤ 1, -2 * sqrt(x))