Let/(/) = '^v^J Rj denote the denominator of Equation (5.7).

7=1

(a) Show that V = -4r^. /(O

(b) Another concept sometimes encountered is the convexity, f"( '\

defined by c = r^J . Show that the derivative of v with

/(O _

respect to / is equal to v^ — c.

AppendixLO1