T427

f(x) = If[0 ≤ x ≤ (2 * π), (x * sin(x))]
keskipistesäänto = RectangleSum(f, 0, (2 * π), 3, 0.5)
g(x) = abs(f(x))
keskipistesäänto_2 = RectangleSum(g, 0, (2 * π), 3, 0.5)
a = Integral(g, 0, (2 * π))
teksti2 = LaTeX(f, true, true)
teksti3 = LaTeX(g, true, true)