f(x)=ax²

a = 0.4 (slider from -20 to 20, step 0.1)
f(x) = (a * x^(2))
Sommet = Extremum(f)
texte1 = LaTeX(f, true, true)
A: (2, f(2))
B: (4, f(4))
C: (8, f(8))
D: (-2, f(-2))
E: (-4, f(-4))
F: (-8, f(-8))