23
V(x) = x(3 – 2x) (8 – 2x)
= 4x3 – 22x2 + 24x
Therefore
2
V ( )
12
44
24
4(
3)(3
2)
V ( )
24
44
x
x
x
x
x
x
x
 ′
=
−
+
=
−
−
 ′′
=
−

Now
V′(x) = 0 gives 
x =3, 32 But x ≠ 3 (Why )
Thus, we have
x =32 Now 
2
2
V
24
44
28
0
3
3




′′
=
−
= −
<







