A:(-1, -1 / 9 - 1 / 3 + 1)
B:(0, 0)
C:(1, 1 / 9 - 1 / 3 - 1)
D:(2, 8 / 9 - 4 / 3 - 2)
f = Polynomial({A, B, C, D})
f' = Derivative(f)
f'' = Derivative(f, 2)
P_1 = (NaN, NaN)
E: (x(P_1), f'(x(P_1)))
F: (x(P_1), f''(x(P_1)))
a = Segment(P_1, E)
b = Segment(E, F)
texto1 = LaTeX(f, true, true)
texto2 = LaTeX(f'', true, true)
P = Point(f)
G: (x(P), f''(x(P)))
c = Segment(P, G)
texto3: "f''(" + (x(P)) + ")=" + (f''(x(P))) + ""