V = 866 (slider from -5 to 1000)
a(x) = (4 * x) + 1
b(x) = x + V / x^(2) + 2
A(x) = If[x > 0, (a(x) * b(x))]
A1(x) = A'(x)
c: b(8.19)
d: A(8.19)
l1 = Solve(A1(x) = 0)
f(x) = (((4 * x) + 1) * (x + V / x^(2) + 2))
f1(x) = f'(x)
l2 = Solve(f1(x) = 0)
e: b(7.38)
g: f(7.28)
T: (7.38, A(7.38))