f(x) = 1.0 / 100.0 * x^(3.0) + 1.0 / 50.0 * x^(2.0) - 7.0 / 10.0 * x + 5.0
c = Segment((-10.0, 0.0), (10.0, 0.0))
B = Point(c)
A = Point(c)
a: x(A)
b: x(B)
n = 10 (slider from 1 to 100, step 1)
U = LowerSum(f, a, b, n)
O = UpperSum(f, a, b, n)
Text1: "a = " + (x(A))
Text2: "b = " + (x(B))
Text3: "Obersumme: O_{" + n + "} = " + O
Text4: "Untersumme: U_{" + n + "}  = " + U
D: O - U
Text5: "Differenz: O_{" + n + "}  - U_{" + n + "}  = " + D
E: 0.5 * (O + U)
B1: (x(B) - 0.5, -1.0 * 1.0 * 1.0 * 1.0 * 1.0 * 1.0)
A1: (x(A) - 0.5, -1.0 * 1.0 * 1.0 * 1.0 * 1.0 * 1.0)