| Intuitionistic Logic Explorer |
< Previous
Next >
Nearby theorems |
||
| Mirrors > Home > ILE Home > Th. List > nfre1 | GIF version | ||
| Description: 𝑥 is not free in ∃𝑥 ∈ 𝐴𝜑. (Contributed by NM, 19-Mar-1997.) (Revised by Mario Carneiro, 7-Oct-2016.) |
| Ref | Expression |
|---|---|
| nfre1 | ⊢ Ⅎ𝑥∃𝑥 ∈ 𝐴 𝜑 |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | df-rex 2517 | . 2 ⊢ (∃𝑥 ∈ 𝐴 𝜑 ↔ ∃𝑥(𝑥 ∈ 𝐴 ∧ 𝜑)) | |
| 2 | nfe1 1545 | . 2 ⊢ Ⅎ𝑥∃𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) | |
| 3 | 1, 2 | nfxfr 1523 | 1 ⊢ Ⅎ𝑥∃𝑥 ∈ 𝐴 𝜑 |
| Colors of variables: wff set class |
| Syntax hints: ∧ wa 104 Ⅎwnf 1509 ∃wex 1541 ∈ wcel 2202 ∃wrex 2512 |
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-ia1 106 ax-ia2 107 ax-ia3 108 ax-5 1496 ax-gen 1498 ax-ie1 1542 |
| This theorem depends on definitions: df-bi 117 df-nf 1510 df-rex 2517 |
| This theorem is referenced by: r19.29an 2676 nfiu1 4005 fun11iun 5613 eusvobj2 6014 fodjuomnilemdc 7386 ismkvnex 7397 prarloclem3step 7759 prmuloc2 7830 ltexprlemm 7863 caucvgprprlemaddq 7971 caucvgsrlemgt1 8058 axpre-suploclemres 8164 supinfneg 9873 infsupneg 9874 lbzbi 9894 divalglemeunn 12545 divalglemeuneg 12547 bezoutlemmain 12632 bezout 12645 lss1d 14462 pw1nct 16708 isomninnlem 16745 trirec0 16759 ismkvnnlem 16768 |
| Copyright terms: Public domain | W3C validator |