A B C | Y
---------|---
0 0 0 | 1
0 0 1 | 1
0 1 0 | 1
0 1 1 | 1
1 0 0 | 0
1 0 1 | 1
1 1 0 | 0
1 1 1 | 0
A' + AB'C
(A + B'C)' + (AB + C')'
A'(B'C)' + (AB)'C DeMorgan's Law
A'(B + C') + (A' + B')C Demorgan's Law -- again
A'B + A'C' + A'C + B'C Distributive Rule
A'B + A'(C' + C) + B'C Distributive Rule and Identity Element
A'(B + 1) + (A' + A)B'C Identity Element
A'(B + 1 + B'C) + AB'C Identity Element
A' + AB'C