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| Mirrors > Home > ILE Home > Th. List > Mathboxes > alsconv | GIF version | ||
| Description: There is an equivalence between the two "all some" forms. (Contributed by David A. Wheeler, 22-Oct-2018.) | 
| Ref | Expression | 
|---|---|
| alsconv | ⊢ (∀!𝑥(𝑥 ∈ 𝐴 → 𝜑) ↔ ∀!𝑥 ∈ 𝐴𝜑) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | df-ral 2480 | . . 3 ⊢ (∀𝑥 ∈ 𝐴 𝜑 ↔ ∀𝑥(𝑥 ∈ 𝐴 → 𝜑)) | |
| 2 | 1 | anbi1i 458 | . 2 ⊢ ((∀𝑥 ∈ 𝐴 𝜑 ∧ ∃𝑥 𝑥 ∈ 𝐴) ↔ (∀𝑥(𝑥 ∈ 𝐴 → 𝜑) ∧ ∃𝑥 𝑥 ∈ 𝐴)) | 
| 3 | df-alsc 15723 | . 2 ⊢ (∀!𝑥 ∈ 𝐴𝜑 ↔ (∀𝑥 ∈ 𝐴 𝜑 ∧ ∃𝑥 𝑥 ∈ 𝐴)) | |
| 4 | df-alsi 15722 | . 2 ⊢ (∀!𝑥(𝑥 ∈ 𝐴 → 𝜑) ↔ (∀𝑥(𝑥 ∈ 𝐴 → 𝜑) ∧ ∃𝑥 𝑥 ∈ 𝐴)) | |
| 5 | 2, 3, 4 | 3bitr4ri 213 | 1 ⊢ (∀!𝑥(𝑥 ∈ 𝐴 → 𝜑) ↔ ∀!𝑥 ∈ 𝐴𝜑) | 
| Colors of variables: wff set class | 
| Syntax hints: → wi 4 ∧ wa 104 ↔ wb 105 ∀wal 1362 ∃wex 1506 ∈ wcel 2167 ∀wral 2475 ∀!walsi 15720 ∀!walsc 15721 | 
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-ia1 106 ax-ia2 107 ax-ia3 108 | 
| This theorem depends on definitions: df-bi 117 df-ral 2480 df-alsi 15722 df-alsc 15723 | 
| This theorem is referenced by: (None) | 
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