determine whether the argument is valid or invalid. If it is invalid, select a counterexample.
-1. I • (J $ \lor $ H)
2) I ⊃ ∼J
3) H ≡ (K $ \lor $ I) / K
A) Valid
B) Invalid. Counterexample when H and I are true and J and K are false
C) Invalid. Counterexample when I is true and H, J, and K are false
D) Invalid. Counterexample when H, I, and J are true and K is false
E) Invalid. Counterexample when J is true, and H, I, and K are false

Question

Quizplus · Accepted Answer

Assuming that I is true and J and H are false, the first premise becomes I • ¬H. The second premise becomes I ⊃ ¬J. The third premise becomes ¬K ≡ I. Then, we can conclude that ¬K is true, which means K is false. However, the third premise also implies that H is true since K is false and I is true. This creates a contradiction with the first premise (I • ¬H) and shows that the argument is invalid.

Determine Whether the Argument Is Valid or Invalid ∨ \lor ∨

Determine Whether the Argument Is Valid or Invalid $\lor$