Commun. Korean Math. Soc. 1997 Vol. 12, No. 3, 619-629
S. Elumalai, Y. J. Cho, S. S. Kim University of Madras, Gyeongsang National University, Dongeui University
Abstract : In this paper, we give some properties of the sets $D_z(x_o,$ $G),P_{G,z}(x)$. We also provide the relation between $P_{G,z}(x)$ and G\^ate-aux derivatives.
Keywords : $D_z(x_o,G)$, $P_{G,z}(x)$, G\^ateaux derivatives, Best approximations, $b$-extensions