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| Mirrors > Home > ILE Home > Th. List > nfrexw | GIF version | ||
| Description: Not-free for restricted existential quantification where 𝑥 and 𝑦 are distinct. See nfrexya 2548 for a version with 𝑦 and 𝐴 distinct instead. (Contributed by Jim Kingdon, 30-May-2018.) |
| Ref | Expression |
|---|---|
| nfralxy.1 | ⊢ Ⅎ𝑥𝐴 |
| nfralxy.2 | ⊢ Ⅎ𝑥𝜑 |
| Ref | Expression |
|---|---|
| nfrexw | ⊢ Ⅎ𝑥∃𝑦 ∈ 𝐴 𝜑 |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | nftru 1490 | . . 3 ⊢ Ⅎ𝑦⊤ | |
| 2 | nfralxy.1 | . . . 4 ⊢ Ⅎ𝑥𝐴 | |
| 3 | 2 | a1i 9 | . . 3 ⊢ (⊤ → Ⅎ𝑥𝐴) |
| 4 | nfralxy.2 | . . . 4 ⊢ Ⅎ𝑥𝜑 | |
| 5 | 4 | a1i 9 | . . 3 ⊢ (⊤ → Ⅎ𝑥𝜑) |
| 6 | 1, 3, 5 | nfrexdxy 2541 | . 2 ⊢ (⊤ → Ⅎ𝑥∃𝑦 ∈ 𝐴 𝜑) |
| 7 | 6 | mptru 1382 | 1 ⊢ Ⅎ𝑥∃𝑦 ∈ 𝐴 𝜑 |
| Colors of variables: wff set class |
| Syntax hints: ⊤wtru 1374 Ⅎwnf 1484 Ⅎwnfc 2336 ∃wrex 2486 |
| 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 1471 ax-7 1472 ax-gen 1473 ax-ie1 1517 ax-ie2 1518 ax-4 1534 ax-17 1550 ax-ial 1558 ax-i5r 1559 ax-ext 2188 |
| This theorem depends on definitions: df-bi 117 df-tru 1376 df-nf 1485 df-cleq 2199 df-clel 2202 df-nfc 2338 df-rex 2491 |
| This theorem is referenced by: r19.12 2613 sbcrext 3080 nfuni 3861 nfiunxy 3958 rexxpf 4832 abrexex2g 6217 abrexex2 6221 nfrecs 6405 nfwrd 11039 fimaxre2 11608 nfsum 11738 nfcprod1 11935 nfcprod 11936 bezoutlemmain 12389 ctiunctlemfo 12880 bj-findis 16049 strcollnfALT 16056 |
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