Same chapter3 marksDifficulty: Medium
Simplify the Boolean expression (X + Y)(X + Y′).
Boolean Algebra
3 marksDifficulty: Medium
State and prove De Morgan's two theorems using a truth table.
Original Khojo Papers practice question — not from a past board paper.
Answer
The theorems are (X + Y)′ = X′ · Y′ and (X · Y)′ = X′ + Y′. A truth table with all four combinations of X and Y shows that the columns for each side of both identities agree in every row.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The theorems let a complemented expression be rewritten so that the complement applies only to single variables.
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