Prove:
Majority = ((~A && B && C) || (A && ~B && C) ||
(A && B && ~C) || (A
&& B && C))
|
|
|
|
| (A && ~B && C) |
| (A && B && C) |
|
|---|---|---|---|---|---|---|---|
|
|
|
|
| 0 |
| 0 |
|
|
|
|
|
| 0 |
| 0 |
|
|
|
|
|
| 0 |
| 0 |
|
| 0 | 1 | 1 | 1 | 0 | 0 | 0 | 1 |
| 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 1 | 0 | 1 | 0 | 1 | 0 | 0 | 1 |
| 1 | 1 | 0 | 0 | 0 | 1 | 0 | 1 |
|
|
|
|
| 0 |
| 1 |
|
Look at the equation:
((~A && B && C) || (A && ~B && C) || (A && B && ~C) || (A && B && C))
The first three groups contains two "normal" variables and the NOT
of the other -- i.e., each corresponds to a case of having two true values.
The fourth term corresponds to the case where all three are true.
What is the significance of the NOT terms?
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Last Updated 02/14/2000
© L.Heath, 2000, updated by J.A.N. Lee, 2000/02/10