u v w x f1 f2
0 0 0 0 0 0
0 0 0 1 0 1
0 0 1 0 1 0
0 0 1 1 ? ?
0 1 0 0 0 1
0 1 0 1 1 0
0 1 1 0 0 0
0 1 1 1 ? ?
1 0 0 0 1 0
1 0 0 1 0 0
1 0 1 0 0 1
1 0 1 1 ? ?
1 1 0 0 ? ?
1 1 0 1 ? ?
1 1 1 0 ? ?
1 1 1 1 ? ?
As the unspecified values will never occur, we can give the function either value 0 or 1.
For the time being, letÕs just make them all 0.
Now we can Òread offÓ an expression for each function.
f1 (u,
v, w, x) =
u' v' w x'
+ u' v w' x
+ u v' w' x'