Theorem reximdd 46436

Description: Deduction from Theorem 19.22 of [Margaris] p. 90. (Contributed by Glauco Siliprandi, 5-Feb-2022.)

Hypotheses

Ref	Expression
reximdd.1	⊢ Ⅎ𝑥𝜑
reximdd.2	⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴 ∧ 𝜓) → 𝜒)
reximdd.3	⊢ (𝜑 → ∃𝑥 ∈ 𝐴 𝜓)

Assertion

Ref	Expression
reximdd	⊢ (𝜑 → ∃𝑥 ∈ 𝐴 𝜒)

Proof of Theorem reximdd

Step	Hyp	Ref	Expression
1		reximdd.3	. 2 ⊢ (𝜑 → ∃𝑥 ∈ 𝐴 𝜓)
2		reximdd.1	. . 3 ⊢ Ⅎ𝑥𝜑
3		reximdd.2	. . . 4 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴 ∧ 𝜓) → 𝜒)
4	3	3exp 1137	. . 3 ⊢ (𝜑 → (𝑥 ∈ 𝐴 → (𝜓 → 𝜒)))
5	2, 4	reximdai 3268	. 2 ⊢ (𝜑 → (∃𝑥 ∈ 𝐴 𝜓 → ∃𝑥 ∈ 𝐴 𝜒))
6	1, 5	mpd 16	1 ⊢ (𝜑 → ∃𝑥 ∈ 𝐴 𝜒)

This proof depends on syntax axioms:   → wi 4   ∧ w3a 1103  Ⅎwnf 1816   ∈ wcel 2147  ∃wrex 3090

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1945  ax-6 2002  ax-7 2043  ax-12 2216

This proof depends on definitions:  df-bi 210  df-an 402  df-3an 1105  df-ex 1813  df-nf 1817  df-ral 3081  df-rex 3091

This theorem is used by:  iinss2d  46445  xlimmnfvlem2  47116  xlimmnfv  47117  xlimpnfvlem2  47120  xlimpnfv  47121  fsupdm  48125  finfdm  48129