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Complete the truth table given below to verify the first de morgan law ¬(p ∧ q) ≡ ¬p ∨ ¬q.

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Final Answer:


| p | q | ¬(p ∧ q) | ¬p ∨ ¬q ||---|---|----------|--------|


| T | T | F | F || T | F | T | T || F | T | T | T || F | F | T | T |

Step-by-step explanation:

The truth table demonstrates that
¬(p ∧ q) is equivalent to
¬p ∨ ¬q for all possible truth values of p and q. According to the first De Morgan law, the negation of a conjunction is equivalent to the disjunction of the negations of the individual propositions. In the truth table:

1. When both p and q are true
(T), ¬(p ∧ q) is false (F), and ¬p ∨ ¬qis also false (F).

2. When p is true (T) and q is false
(F), ¬(p ∧ q) is true (T), and ¬p ∨ ¬qis also true (T).

3. When p is false (F) and q is true (T),
¬(p ∧ q) is true (T), and ¬p ∨ ¬q is also true (T).

4. When both p and q are false
(F), ¬(p ∧ q) is true (T), and ¬p ∨ ¬q is also true (T).

Thus, the truth values match for both expressions, confirming the validity of the first De Morgan law
¬(p ∧ q) ≡ ¬p ∨ ¬q.

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