Logics – Tautologies and Contradictions

1. A compound proposition that is always ___________ is called a tautology.
a) True

b) False

2. A compound proposition that is always ___________ is called a contradiction.
a) True
b) False

3. If A is any statement, then which of the following is a tautology?
a) A ∧ F
b) A ∨ F
c) A ¬A
d) A ∧ T

4. If A is any statement, then which of the following is not a contradiction?
a) A ∧ ¬A
b) A F
c) A ∧ F
d) None of mentioned

5. A compound proposition that is neither a tautology nor a contradiction is called a ___________
a) Contingency
b) Equivalence
c) Condition
d) Inference

.

6. ¬ (A q) (A q) is a ___________
a) Tautology
b) Contradiction
c) Contingency
d) None of the mentioned

7. (A ¬A) (q T) is a __________
a) Tautology

b) Contradiction
c) Contingency
d) None of the mentioned

8. A ¬(A (A T)) is always __________
a) True
b) False

.

9. (A F) (A T) is always _________
a) True

b) False

10. A → (A ∨ q) is a __________
a) Tautology

b) Contradiction
c) Contingency
d) None of the mentioned