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Mirrors > Home > ILE Home > Th. List > nfif | GIF version |
Description: Bound-variable hypothesis builder for a conditional operator. (Contributed by NM, 16-Feb-2005.) (Proof shortened by Andrew Salmon, 26-Jun-2011.) |
Ref | Expression |
---|---|
nfif.1 | ⊢ Ⅎ𝑥𝜑 |
nfif.2 | ⊢ Ⅎ𝑥𝐴 |
nfif.3 | ⊢ Ⅎ𝑥𝐵 |
Ref | Expression |
---|---|
nfif | ⊢ Ⅎ𝑥if(𝜑, 𝐴, 𝐵) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | nfif.1 | . . . 4 ⊢ Ⅎ𝑥𝜑 | |
2 | 1 | a1i 9 | . . 3 ⊢ (⊤ → Ⅎ𝑥𝜑) |
3 | nfif.2 | . . . 4 ⊢ Ⅎ𝑥𝐴 | |
4 | 3 | a1i 9 | . . 3 ⊢ (⊤ → Ⅎ𝑥𝐴) |
5 | nfif.3 | . . . 4 ⊢ Ⅎ𝑥𝐵 | |
6 | 5 | a1i 9 | . . 3 ⊢ (⊤ → Ⅎ𝑥𝐵) |
7 | 2, 4, 6 | nfifd 3469 | . 2 ⊢ (⊤ → Ⅎ𝑥if(𝜑, 𝐴, 𝐵)) |
8 | 7 | mptru 1325 | 1 ⊢ Ⅎ𝑥if(𝜑, 𝐴, 𝐵) |
Colors of variables: wff set class |
Syntax hints: ⊤wtru 1317 Ⅎwnf 1421 Ⅎwnfc 2245 ifcif 3444 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-ia1 105 ax-ia2 106 ax-ia3 107 ax-in1 588 ax-in2 589 ax-io 683 ax-5 1408 ax-7 1409 ax-gen 1410 ax-ie1 1454 ax-ie2 1455 ax-8 1467 ax-10 1468 ax-11 1469 ax-i12 1470 ax-bndl 1471 ax-4 1472 ax-17 1491 ax-i9 1495 ax-ial 1499 ax-i5r 1500 ax-ext 2099 |
This theorem depends on definitions: df-bi 116 df-tru 1319 df-fal 1322 df-nf 1422 df-sb 1721 df-clab 2104 df-cleq 2110 df-clel 2113 df-nfc 2247 df-if 3445 |
This theorem is referenced by: nfsum1 11093 nfsum 11094 sumrbdclem 11113 summodclem2a 11118 zsumdc 11121 fsum3 11124 isumss 11128 isumss2 11130 fsum3cvg2 11131 |
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