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| Mirrors > Home > NFE Home > Th. List > reximdvai | GIF version | ||
| Description: Deduction quantifying both antecedent and consequent, based on Theorem 19.22 of [Margaris] p. 90. (Contributed by NM, 14-Nov-2002.) | 
| Ref | Expression | 
|---|---|
| reximdvai.1 | ⊢ (φ → (x ∈ A → (ψ → χ))) | 
| Ref | Expression | 
|---|---|
| reximdvai | ⊢ (φ → (∃x ∈ A ψ → ∃x ∈ A χ)) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | nfv 1619 | . 2 ⊢ Ⅎxφ | |
| 2 | reximdvai.1 | . 2 ⊢ (φ → (x ∈ A → (ψ → χ))) | |
| 3 | 1, 2 | reximdai 2723 | 1 ⊢ (φ → (∃x ∈ A ψ → ∃x ∈ A χ)) | 
| Colors of variables: wff setvar class | 
| Syntax hints: → wi 4 ∈ wcel 1710 ∃wrex 2616 | 
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1546 ax-5 1557 ax-17 1616 ax-9 1654 ax-8 1675 ax-11 1746 | 
| This theorem depends on definitions: df-bi 177 df-an 360 df-ex 1542 df-nf 1545 df-ral 2620 df-rex 2621 | 
| This theorem is referenced by: reximdv 2726 reximdva 2727 reuind 3040 | 
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