Binary-to-minterm conversion (variable order A, B, C, D): The 4-bit pattern 1010 corresponds to which product (minterm) term in SOP form?
-
AA * B' * C * D'
-
BA' * B * C' * D
-
CA * B * C' * D
-
DA' * B' * C * D'
-
EA * B' * C' * D
Answer
Correct Answer: A * B' * C * D'
Explanation
Introduction / Context:This item checks your ability to translate a binary assignment into a minterm (product) for a specified variable order. In standard SOP, each minterm includes all variables either complemented or uncomplemented to represent one unique row of the truth table.
Given Data / Assumptions:
- Variable order is A, B, C, D (left to right).
- Binary 1010 means A=1, B=0, C=1, D=0.
- We want the corresponding product term.
Concept / Approach:For a variable equal to 1, use the variable uncomplemented; for 0, use its complement. Combine all variables with * to form the minterm.
Step-by-Step Solution:
Step 1: Map bits: A=1 → A; B=0 → B'; C=1 → C; D=0 → D'.Step 2: Form the minterm: A * B' * C * D'.Step 3: Verify that the term uniquely identifies the 1010 row.Verification / Alternative check:This corresponds to minterm m10 (if A is the MSB). Expanding to decimal index confirms consistency with A B C D = 1 0 1 0.
Why Other Options Are Wrong:
A' * B * C' * D: Bit pattern 0 1 0 1, not 1 0 1 0.A * B * C' * D: Uses B=1 and D=1, contradicting 1010.A' * B' * C * D': Uses A=0, not 1.A * B' * C' * D: Uses C=0 and D=1, not 1 and 0.Common Pitfalls:Forgetting the stated variable order or flipping complement rules.
Final Answer:A * B' * C * D'