ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  dm0rn0 GIF version

Theorem dm0rn0 4804
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.)
Assertion
Ref Expression
dm0rn0 (dom 𝐴 = ∅ ↔ ran 𝐴 = ∅)

Proof of Theorem dm0rn0
Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 alnex 1479 . . . . . 6 (∀𝑥 ¬ ∃𝑦 𝑥𝐴𝑦 ↔ ¬ ∃𝑥𝑦 𝑥𝐴𝑦)
2 excom 1644 . . . . . 6 (∃𝑥𝑦 𝑥𝐴𝑦 ↔ ∃𝑦𝑥 𝑥𝐴𝑦)
31, 2xchbinx 672 . . . . 5 (∀𝑥 ¬ ∃𝑦 𝑥𝐴𝑦 ↔ ¬ ∃𝑦𝑥 𝑥𝐴𝑦)
4 alnex 1479 . . . . 5 (∀𝑦 ¬ ∃𝑥 𝑥𝐴𝑦 ↔ ¬ ∃𝑦𝑥 𝑥𝐴𝑦)
53, 4bitr4i 186 . . . 4 (∀𝑥 ¬ ∃𝑦 𝑥𝐴𝑦 ↔ ∀𝑦 ¬ ∃𝑥 𝑥𝐴𝑦)
6 noel 3398 . . . . . 6 ¬ 𝑥 ∈ ∅
76nbn 689 . . . . 5 (¬ ∃𝑦 𝑥𝐴𝑦 ↔ (∃𝑦 𝑥𝐴𝑦𝑥 ∈ ∅))
87albii 1450 . . . 4 (∀𝑥 ¬ ∃𝑦 𝑥𝐴𝑦 ↔ ∀𝑥(∃𝑦 𝑥𝐴𝑦𝑥 ∈ ∅))
9 noel 3398 . . . . . 6 ¬ 𝑦 ∈ ∅
109nbn 689 . . . . 5 (¬ ∃𝑥 𝑥𝐴𝑦 ↔ (∃𝑥 𝑥𝐴𝑦𝑦 ∈ ∅))
1110albii 1450 . . . 4 (∀𝑦 ¬ ∃𝑥 𝑥𝐴𝑦 ↔ ∀𝑦(∃𝑥 𝑥𝐴𝑦𝑦 ∈ ∅))
125, 8, 113bitr3i 209 . . 3 (∀𝑥(∃𝑦 𝑥𝐴𝑦𝑥 ∈ ∅) ↔ ∀𝑦(∃𝑥 𝑥𝐴𝑦𝑦 ∈ ∅))
13 abeq1 2267 . . 3 ({𝑥 ∣ ∃𝑦 𝑥𝐴𝑦} = ∅ ↔ ∀𝑥(∃𝑦 𝑥𝐴𝑦𝑥 ∈ ∅))
14 abeq1 2267 . . 3 ({𝑦 ∣ ∃𝑥 𝑥𝐴𝑦} = ∅ ↔ ∀𝑦(∃𝑥 𝑥𝐴𝑦𝑦 ∈ ∅))
1512, 13, 143bitr4i 211 . 2 ({𝑥 ∣ ∃𝑦 𝑥𝐴𝑦} = ∅ ↔ {𝑦 ∣ ∃𝑥 𝑥𝐴𝑦} = ∅)
16 df-dm 4597 . . 3 dom 𝐴 = {𝑥 ∣ ∃𝑦 𝑥𝐴𝑦}
1716eqeq1i 2165 . 2 (dom 𝐴 = ∅ ↔ {𝑥 ∣ ∃𝑦 𝑥𝐴𝑦} = ∅)
18 dfrn2 4775 . . 3 ran 𝐴 = {𝑦 ∣ ∃𝑥 𝑥𝐴𝑦}
1918eqeq1i 2165 . 2 (ran 𝐴 = ∅ ↔ {𝑦 ∣ ∃𝑥 𝑥𝐴𝑦} = ∅)
2015, 17, 193bitr4i 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
  Copyright terms: Public domain W3C validator