Difficulty: Easy
Correct Answer: Correct
Explanation:
Introduction / Context:
AND and NAND are tightly linked: a NAND is an AND with an inversion at its output. Recognizing this relationship helps with quick truth-table derivations, hardware substitutions, and De Morgan transformations when optimizing logic.
Given Data / Assumptions:
Concept / Approach:
Define the functions: AND output is F = A · B. NAND output is G = NOT(A · B). Clearly, G = NOT(F). Therefore, for each input pair, the NAND’s output is the complement of the AND’s output. This holds for all combinations: 00, 01, 10 produce F=0 → G=1; 11 produces F=1 → G=0.
Step-by-Step Solution:
Verification / Alternative check:
Create a small table: inputs 00,01,10 → F=0 so G=1; input 11 → F=1 so G=0. Every row shows inversion, confirming the statement conclusively.
Why Other Options Are Wrong:
“Incorrect” contradicts the formal definitions. Claims about rise times or logic families (TTL vs CMOS) concern implementation details and do not alter the Boolean relationship.
Common Pitfalls:
Forgetting that NAND is simply AND plus an output inversion; mixing up NAND with NOR (which is the inversion of OR).
Final Answer:
Correct
Discussion & Comments