a = -2 (slider from -5 to 5, step 0.01)
b = 3 (slider from -5 to 5, step 0.1)
c = 3 (slider from -5 to 5, step 0.1)
d = -1.5 (slider from -5 to 5, step 0.01)
A = (1, -2)
f(x) = (((d * (x - a)) * (x - b)) * (x - c))