Note the Connection
f (u, v, w, x) =
                       u v' w ' x'

      + u' v w ' x

                    + u' v' w x'
u v w x  f
0 0 0 0  0
0 0 0 1  0
0 0 1 0  1
0 0 1 1  0
0 1 0 0  0
0 1 0 1  1
0 1 1 0  0
0 1 1 1  0
1 0 0 0  1
1 0 0 1  0
1 0 1 0  0
1 0 1 1  0
1 1 0 0  0
1 1 0 1  0
1 1 1 0  0
1 1 1 1  0
Read off each primed variable as 0, each unprimed as 1.