t = 1 (slider from 0 to 1, step 0.05)
A = (-2, 0)
B = (0, 4)
C = (2, 0)
G: t^(2) A + 2 t * (1 - t) B + (1 - t)^(2) C
f(x) = (x + 2) * (x - 2) 1 / (-2)