Convert and expand to canonical SOP form Given the Boolean expression LM + M(NO + PQ), convert it explicitly into a sum-of-products (SOP) expression by distributing terms and listing the distinct product terms.
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ALM + MNOPQ
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BL + MNO + MPQ
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CLM + M + NO + MPQ
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DLM + MNO + MPQ
Answer
Correct Answer: LM + MNO + MPQ
Explanation
Introduction / Context:Sum-of-products (SOP) form is widely used in digital design because it maps naturally to two-level AND–OR implementations and to programmable logic arrays. Converting any given Boolean expression into SOP ensures that each term is a product (AND) of literals, summed (ORed) together.
Given Data / Assumptions:
- Expression: LM + M(NO + PQ).
- Operators: adjacency = AND, “+” = OR.
- No complements are shown; all literals are in positive form unless implied.
Concept / Approach:To obtain SOP, first expand any parentheses using the distributive property: X(Y + Z) = XY + XZ. Then collect the resulting product terms. Each product term is an AND of literals; the final expression is an OR of these products.
Step-by-Step Solution:
Start with: LM + M(NO + PQ).Distribute M across the parenthesis: M * NO + M * PQ → MNO + MPQ.Include the standalone product: LM.Final SOP: LM + MNO + MPQ.Verification / Alternative check:Each term is a product of literals (LM, MNO, MPQ). There are no sums inside products, so it satisfies SOP. A quick truth-table spot check on a few input combinations confirms functional equivalence before and after expansion.
Why Other Options Are Wrong:
- LM + MNOPQ: Introduces an incorrect five-literal term by multiplying N, O, P, and Q together.
- L + MNO + MPQ: Drops M from LM and incorrectly replaces it with L alone.
- LM + M + NO + MPQ: NO is not gated by M, and “M” as a standalone term alters the function.
Common Pitfalls:Forgetting to distribute to all terms; accidentally multiplying all symbols together; or incorrectly simplifying by removing necessary literals. Always keep track of each literal during distribution.
Final Answer:LM + MNO + MPQ