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| Mirrors > Home > ILE Home > Th. List > fvprc | GIF version | ||
| Description: A function's value at a proper class is the empty set. (Contributed by NM, 20-May-1998.) | 
| Ref | Expression | 
|---|---|
| fvprc | ⊢ (¬ 𝐴 ∈ V → (𝐹‘𝐴) = ∅) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | brprcneu 5551 | . 2 ⊢ (¬ 𝐴 ∈ V → ¬ ∃!𝑥 𝐴𝐹𝑥) | |
| 2 | tz6.12-2 5549 | . 2 ⊢ (¬ ∃!𝑥 𝐴𝐹𝑥 → (𝐹‘𝐴) = ∅) | |
| 3 | 1, 2 | syl 14 | 1 ⊢ (¬ 𝐴 ∈ V → (𝐹‘𝐴) = ∅) | 
| Colors of variables: wff set class | 
| Syntax hints: ¬ wn 3 → wi 4 = wceq 1364 ∃!weu 2045 ∈ wcel 2167 Vcvv 2763 ∅c0 3450 class class class wbr 4033 ‘cfv 5258 | 
| 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-in1 615 ax-in2 616 ax-io 710 ax-5 1461 ax-7 1462 ax-gen 1463 ax-ie1 1507 ax-ie2 1508 ax-8 1518 ax-10 1519 ax-11 1520 ax-i12 1521 ax-bndl 1523 ax-4 1524 ax-17 1540 ax-i9 1544 ax-ial 1548 ax-i5r 1549 ax-14 2170 ax-ext 2178 ax-sep 4151 ax-pow 4207 ax-setind 4573 | 
| This theorem depends on definitions: df-bi 117 df-3an 982 df-tru 1367 df-fal 1370 df-nf 1475 df-sb 1777 df-eu 2048 df-mo 2049 df-clab 2183 df-cleq 2189 df-clel 2192 df-nfc 2328 df-ne 2368 df-ral 2480 df-rex 2481 df-v 2765 df-dif 3159 df-un 3161 df-in 3163 df-ss 3170 df-nul 3451 df-pw 3607 df-sn 3628 df-pr 3629 df-op 3631 df-uni 3840 df-br 4034 df-iota 5219 df-fv 5266 | 
| This theorem is referenced by: fv2prc 5595 | 
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