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Question:

If (p ∧ ¬q) ∧ (p ∧ r) → ¬p ∨ q is false, then the truth values of p, q, and r are, respectively.

F,T,F

T,T,T

F,F,F

T,F,T

Solution:

The truth table for the (p ∧ ¬q) ∧ (p ∧ r) → ¬p ∨ q is:

p q r ¬q p ∧ ¬q p ∧ r (p ∧ ¬q) ∧ (p ∧ r) ¬p ¬p ∨ q (p ∧ ¬q) ∧ (p ∧ r) → ¬p ∨ q
1 1 1 0 0 1 0 0 1 1
1 0 1 1 1 1 1 0 0 0
1 1 0 0 0 0 0 0 1 1
1 0 0 1 1 0 0 0 0 1
0 1 1 0 0 0 0 1 1 1
0 0 1 1 0 0 0 1 1 1
0 1 0 0 0 0 0 1 1 1
0 0 0 1 0 0 0 1 1 1

Only when p is true, q is false, and r is true, the expression (p ∧ ¬q) ∧ (p ∧ r) → ¬p ∨ q is false. Therefore, the truth values of p, q, and r are, respectively, T, F, T.