a = 1 (slider from -5 to 5, step 0.1)
p = 3 (slider from -5 to 5, step 0.1)
q = -1.8 (slider from -5 to 5, step 0.1)
f(x) = a * (x - p)^(2.0) + q
GY_1, GY_2 = Root(f)
SZÉ = Extremum(f)