e = 2.718281828459045
c = 0 (slider from 0 to 2, step 0.01)
Anzahl = 6 (slider from 1 to 100, step 1)
f = Function(x^(2), 0, 10)
a = UpperSum(f, 0, 4, Anzahl)
b = LowerSum(f, 0, 4, Anzahl)