1. (∃X)(Gx • ∼Hx) ≡ (∃X)(Hx • ∼Ix)

question 90

Multiple Choice

1. (∃x) (Gx • ∼Hx) ≡ (∃x) (Hx • ∼Ix)
2. (∀x) (Hx ⊃ Ix)
-Which of the following propositions is an immediate (one-step) consequence in M of the given premises?

• A) Ga • ∼Ha ≡ (∃x)(Hx • ∼Ix)
• B) (∃x)(Gx • ∼Hx) ≡ ∼(∀x)∼(Hx • ∼Ix)
• C) ∼(∀x)(Gx • ∼Hx) ≡ (∃x)(Hx • ∼Ix)
• D) Hc ⊃ Ia
• E) (Ga • ∼Ha) ≡ (Ha • ∼Ia)