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Mirrors > Home > ILE Home > Th. List > dm0rn0 | GIF version |
Description: An empty domain implies an empty range. For a similar theorem for whether the domain and range are inhabited, see dmmrnm 4806. (Contributed by NM, 21-May-1998.) |
Ref | Expression |
---|---|
dm0rn0 | ⊢ (dom 𝐴 = ∅ ↔ ran 𝐴 = ∅) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | alnex 1479 | . . . . . 6 ⊢ (∀𝑥 ¬ ∃𝑦 𝑥𝐴𝑦 ↔ ¬ ∃𝑥∃𝑦 𝑥𝐴𝑦) | |
2 | excom 1644 | . . . . . 6 ⊢ (∃𝑥∃𝑦 𝑥𝐴𝑦 ↔ ∃𝑦∃𝑥 𝑥𝐴𝑦) | |
3 | 1, 2 | xchbinx 672 | . . . . 5 ⊢ (∀𝑥 ¬ ∃𝑦 𝑥𝐴𝑦 ↔ ¬ ∃𝑦∃𝑥 𝑥𝐴𝑦) |
4 | alnex 1479 | . . . . 5 ⊢ (∀𝑦 ¬ ∃𝑥 𝑥𝐴𝑦 ↔ ¬ ∃𝑦∃𝑥 𝑥𝐴𝑦) | |
5 | 3, 4 | bitr4i 186 | . . . 4 ⊢ (∀𝑥 ¬ ∃𝑦 𝑥𝐴𝑦 ↔ ∀𝑦 ¬ ∃𝑥 𝑥𝐴𝑦) |
6 | noel 3398 | . . . . . 6 ⊢ ¬ 𝑥 ∈ ∅ | |
7 | 6 | nbn 689 | . . . . 5 ⊢ (¬ ∃𝑦 𝑥𝐴𝑦 ↔ (∃𝑦 𝑥𝐴𝑦 ↔ 𝑥 ∈ ∅)) |
8 | 7 | albii 1450 | . . . 4 ⊢ (∀𝑥 ¬ ∃𝑦 𝑥𝐴𝑦 ↔ ∀𝑥(∃𝑦 𝑥𝐴𝑦 ↔ 𝑥 ∈ ∅)) |
9 | noel 3398 | . . . . . 6 ⊢ ¬ 𝑦 ∈ ∅ | |
10 | 9 | nbn 689 | . . . . 5 ⊢ (¬ ∃𝑥 𝑥𝐴𝑦 ↔ (∃𝑥 𝑥𝐴𝑦 ↔ 𝑦 ∈ ∅)) |
11 | 10 | albii 1450 | . . . 4 ⊢ (∀𝑦 ¬ ∃𝑥 𝑥𝐴𝑦 ↔ ∀𝑦(∃𝑥 𝑥𝐴𝑦 ↔ 𝑦 ∈ ∅)) |
12 | 5, 8, 11 | 3bitr3i 209 | . . 3 ⊢ (∀𝑥(∃𝑦 𝑥𝐴𝑦 ↔ 𝑥 ∈ ∅) ↔ ∀𝑦(∃𝑥 𝑥𝐴𝑦 ↔ 𝑦 ∈ ∅)) |
13 | abeq1 2267 | . . 3 ⊢ ({𝑥 ∣ ∃𝑦 𝑥𝐴𝑦} = ∅ ↔ ∀𝑥(∃𝑦 𝑥𝐴𝑦 ↔ 𝑥 ∈ ∅)) | |
14 | abeq1 2267 | . . 3 ⊢ ({𝑦 ∣ ∃𝑥 𝑥𝐴𝑦} = ∅ ↔ ∀𝑦(∃𝑥 𝑥𝐴𝑦 ↔ 𝑦 ∈ ∅)) | |
15 | 12, 13, 14 | 3bitr4i 211 | . 2 ⊢ ({𝑥 ∣ ∃𝑦 𝑥𝐴𝑦} = ∅ ↔ {𝑦 ∣ ∃𝑥 𝑥𝐴𝑦} = ∅) |
16 | df-dm 4597 | . . 3 ⊢ dom 𝐴 = {𝑥 ∣ ∃𝑦 𝑥𝐴𝑦} | |
17 | 16 | eqeq1i 2165 | . 2 ⊢ (dom 𝐴 = ∅ ↔ {𝑥 ∣ ∃𝑦 𝑥𝐴𝑦} = ∅) |
18 | dfrn2 4775 | . . 3 ⊢ ran 𝐴 = {𝑦 ∣ ∃𝑥 𝑥𝐴𝑦} | |
19 | 18 | eqeq1i 2165 | . 2 ⊢ (ran 𝐴 = ∅ ↔ {𝑦 ∣ ∃𝑥 𝑥𝐴𝑦} = ∅) |
20 | 15, 17, 19 | 3bitr4i 211 | 1 ⊢ (dom 𝐴 = ∅ ↔ ran 𝐴 = ∅) |
Colors of variables: wff set class |
Syntax hints: ¬ wn 3 ↔ wb 104 ∀wal 1333 = wceq 1335 ∃wex 1472 ∈ wcel 2128 {cab 2143 ∅c0 3394 class class class wbr 3966 dom cdm 4587 ran crn 4588 |
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 604 ax-in2 605 ax-io 699 ax-5 1427 ax-7 1428 ax-gen 1429 ax-ie1 1473 ax-ie2 1474 ax-8 1484 ax-10 1485 ax-11 1486 ax-i12 1487 ax-bndl 1489 ax-4 1490 ax-17 1506 ax-i9 1510 ax-ial 1514 ax-i5r 1515 ax-14 2131 ax-ext 2139 ax-sep 4083 ax-pow 4136 ax-pr 4170 |
This theorem depends on definitions: df-bi 116 df-3an 965 df-tru 1338 df-fal 1341 df-nf 1441 df-sb 1743 df-eu 2009 df-mo 2010 df-clab 2144 df-cleq 2150 df-clel 2153 df-nfc 2288 df-v 2714 df-dif 3104 df-un 3106 df-in 3108 df-ss 3115 df-nul 3395 df-pw 3545 df-sn 3566 df-pr 3567 df-op 3569 df-br 3967 df-opab 4027 df-cnv 4595 df-dm 4597 df-rn 4598 |
This theorem is referenced by: rn0 4843 relrn0 4849 imadisj 4949 ndmima 4964 f00 5362 f0rn0 5365 2nd0 6094 map0b 6633 |
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