The Boolean function x'y' + xy + x'y is equivalent to
2004
The Boolean function x'y' + xy + x'y is equivalent to
Answer: D. x' + y — ConceptA sum-of-products Boolean expression can be reduced using three standard identities: the complement law A + A' = 1, the identity law 1·A = A, and the…
- A.
x' + y'
- B.
x + y
- C.
x + y'
- D.
x' + y
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Correct answer: D
Concept
A sum-of-products Boolean expression can be reduced using three standard identities: the complement law A + A' = 1, the identity law 1·A = A, and the absorption identity A + A'B = A + B (derivable from the distributive form (A + A')(A + B) = A + B). Grouping terms that share a common literal lets a longer expression collapse step by step into an equivalent, simpler form.
Application
Group the two terms sharing the factor x': x'y' + x'y = x'(y' + y).
Apply the complement law y' + y = 1, so x'(y' + y) = x'·1 = x'.
The original expression x'y' + xy + x'y therefore reduces to x' + xy.
Apply the absorption identity A + A'B = A + B with A = x', B = y: x' + xy = x' + y.
Cross-check
An independent truth-table check confirms the reduction holds for every input combination:
x | y | x'y' + xy + x'y | x' + y |
|---|---|---|---|
0 | 0 | 1 | 1 |
0 | 1 | 1 | 1 |
1 | 0 | 0 | 0 |
1 | 1 | 1 | 1 |
Both columns match on all four rows, confirming the simplification.
Result: x'y' + xy + x'y is equivalent to x' + y.
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