Metamath Proof Explorer


Theorem reximdv2

Description: Deduction quantifying both antecedent and consequent, based on Theorem 19.22 of Margaris p. 90. (Contributed by NM, 17-Sep-2003)

Ref Expression
Hypothesis reximdv2.1 ( 𝜑 → ( ( 𝑥𝐴𝜓 ) → ( 𝑥𝐵𝜒 ) ) )
Assertion reximdv2 ( 𝜑 → ( ∃ 𝑥𝐴 𝜓 → ∃ 𝑥𝐵 𝜒 ) )

Proof

Step Hyp Ref Expression
1 reximdv2.1 ( 𝜑 → ( ( 𝑥𝐴𝜓 ) → ( 𝑥𝐵𝜒 ) ) )
2 1 eximdv ( 𝜑 → ( ∃ 𝑥 ( 𝑥𝐴𝜓 ) → ∃ 𝑥 ( 𝑥𝐵𝜒 ) ) )
3 df-rex ( ∃ 𝑥𝐴 𝜓 ↔ ∃ 𝑥 ( 𝑥𝐴𝜓 ) )
4 df-rex ( ∃ 𝑥𝐵 𝜒 ↔ ∃ 𝑥 ( 𝑥𝐵𝜒 ) )
5 2 3 4 3imtr4g ( 𝜑 → ( ∃ 𝑥𝐴 𝜓 → ∃ 𝑥𝐵 𝜒 ) )