1] There is need for a slight correction in eq 4.79 in the convex optimization notes at http://www.cse.iitb.ac.in/~cs725/notes/classNotes/BasicsOfConvexOptimization.pdf. It should have been

.... = \nable (f(x) + \sum_{i=1}^m \lambda_i g_i(\(x)).....

instead it is

.... = \nable (f(x) - \sum_{i=1}^m \lambda_i g_i(\(x)).....

This mistake is not there in the preceding discussion.

2]