Difficulty: Easy
Correct Answer: Incorrect
Explanation:
Introduction / Context:Logic comparisons such as equality, greater-than, or parity checks are core tasks for digital hardware. The statement claims digital circuits cannot compare because they have only two values at any instant—a misunderstanding of how multi-bit logic and Boolean operations work.
Given Data / Assumptions:
Concept / Approach:Digital comparators cascade basic gates to implement functions like A == B, A > B, and A < B. Even though each signal is binary, networks of gates can evaluate conditions over multiple bits in parallel. CPUs, ALUs, and dedicated comparator ICs are practical embodiments of this principle.
Step-by-Step Solution:
Define comparison as a Boolean function over bit vectors.Implement equality by XORing each bit pair and ORing the results, then invert for equality.Implement greater-than via prioritized subtraction/propagate logic.Conclude that digital logic readily performs comparisons.Verification / Alternative check:Standard ICs (e.g., 74xx85 magnitude comparators) prove that two-value logic readily implements complex comparisons reliably and quickly.
Why Other Options Are Wrong:
Common Pitfalls:Mistaking signal discreteness (two levels) for functional limitation; in fact, Boolean algebra enables arbitrary logic, including comparisons, with binary signals.
Final Answer:Incorrect
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