- #1
programmer123
- 31
- 0
Hello,
I am having particular trouble with the below problem. We are using http://studygig.com/uploads/materials/math1090_mathematical_logi.pdf and we must prove this statement using Hilbert style or Equational style proof (first-order logic), but any proof of any type would point me in the right direction.
(∀x)(A→B) ≡ ((∃x)A) → B
So far I have tried to use Ping-Pong Theorem to prove that
1. (∀x)(A→B) → (((∃x)A) → B)
and
2. (((∃x)A) → B) → (∀x)(A→B)
but I can't prove either 1. or 2.
If anyone could provide insight, I would appreciate it.
I am having particular trouble with the below problem. We are using http://studygig.com/uploads/materials/math1090_mathematical_logi.pdf and we must prove this statement using Hilbert style or Equational style proof (first-order logic), but any proof of any type would point me in the right direction.
(∀x)(A→B) ≡ ((∃x)A) → B
So far I have tried to use Ping-Pong Theorem to prove that
1. (∀x)(A→B) → (((∃x)A) → B)
and
2. (((∃x)A) → B) → (∀x)(A→B)
but I can't prove either 1. or 2.
If anyone could provide insight, I would appreciate it.
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