Q. 22 Consider the first-order logic sentence
F: ∀ x (∃ y R(x,y)).
Assuming non-empty logical domains, which of the sentences below are implied by F?
I. ∃y (∃x R(x,y))
II. ∃y (∀x R(x,y))
III. ∀y (∃x R(x,y))
IV. ∼∃x (∀y R(x,y))
(A) IV only
(B) I and IV only
(C) II only
(D) II and III only
Answer: (B)
Explanation:
