b = 1 (slider from -2 to 2, step 0.1)
a = 0.1 (slider from -1 to 1, step 0.1)
f(x) = a * (x - 1.0) * (b * x - b) * (b * x - b * 5.0)
f'(x) = f'(x)
P = Point(f)
A: (x(P), f'(x(P)))
c = Segment(A, P)
f''(x) = f''(x)
B: (x(P), f''(x(P)))
d = Segment(B, P)