4 Apply vectorial derivatives in order to verify whether given functions f1(x) and f2(x) are self-dual functions A logic function is self-dual if and only if

Prove this theorem, identify the number of self-dual functions of n variables, and verify whether given functions f1(x) (4.18) and f2(x) (4.19) are selfdual functions

af (x) Ox = 1.