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Mirrors > Home > ILE Home > Th. List > nfrexxy | GIF version |
Description: Not-free for restricted existential quantification where 𝑥 and 𝑦 are distinct. See nfrexya 2531 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 |
---|---|
nfrexxy | ⊢ Ⅎ𝑥∃𝑦 ∈ 𝐴 𝜑 |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | nftru 1477 | . . 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 2524 | . 2 ⊢ (⊤ → Ⅎ𝑥∃𝑦 ∈ 𝐴 𝜑) |
7 | 6 | mptru 1373 | 1 ⊢ Ⅎ𝑥∃𝑦 ∈ 𝐴 𝜑 |
Colors of variables: wff set class |
Syntax hints: ⊤wtru 1365 Ⅎwnf 1471 Ⅎwnfc 2319 ∃wrex 2469 |
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 1458 ax-7 1459 ax-gen 1460 ax-ie1 1504 ax-ie2 1505 ax-4 1521 ax-17 1537 ax-ial 1545 ax-i5r 1546 ax-ext 2171 |
This theorem depends on definitions: df-bi 117 df-tru 1367 df-nf 1472 df-cleq 2182 df-clel 2185 df-nfc 2321 df-rex 2474 |
This theorem is referenced by: r19.12 2596 sbcrext 3055 nfuni 3830 nfiunxy 3927 rexxpf 4792 abrexex2g 6145 abrexex2 6149 nfrecs 6332 fimaxre2 11267 nfsum 11397 nfcprod1 11594 nfcprod 11595 bezoutlemmain 12031 ctiunctlemfo 12490 bj-findis 15189 strcollnfALT 15196 |
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