Funkcja kwadratowa

Ciąg

a = 0.1 (slider from -5 to 5, step 0.05)
b = -1.5 (slider from -5 to 5, step 0.05)
c = -1 (slider from -5 to 5, step 0.05)
f(x) = (a * x^(2)) + (b * x) + c
l = Sequence((n, (a * n^(2)) + (b * n) + c), n, 1, 20)
d = true
e = true