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Mirrors > Home > MPE Home > Th. List > f1domg | Structured version Visualization version GIF version |
Description: The domain of a one-to-one function is dominated by its codomain. (Contributed by NM, 4-Sep-2004.) |
Ref | Expression |
---|---|
f1domg | ⊢ (𝐵 ∈ 𝐶 → (𝐹:𝐴–1-1→𝐵 → 𝐴 ≼ 𝐵)) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | f1f 6804 | . . . . 5 ⊢ (𝐹:𝐴–1-1→𝐵 → 𝐹:𝐴⟶𝐵) | |
2 | f1dmex 7979 | . . . . 5 ⊢ ((𝐹:𝐴–1-1→𝐵 ∧ 𝐵 ∈ 𝐶) → 𝐴 ∈ V) | |
3 | fex 7245 | . . . . 5 ⊢ ((𝐹:𝐴⟶𝐵 ∧ 𝐴 ∈ V) → 𝐹 ∈ V) | |
4 | 1, 2, 3 | syl2an2r 685 | . . . 4 ⊢ ((𝐹:𝐴–1-1→𝐵 ∧ 𝐵 ∈ 𝐶) → 𝐹 ∈ V) |
5 | 4 | expcom 413 | . . 3 ⊢ (𝐵 ∈ 𝐶 → (𝐹:𝐴–1-1→𝐵 → 𝐹 ∈ V)) |
6 | f1eq1 6799 | . . . 4 ⊢ (𝑓 = 𝐹 → (𝑓:𝐴–1-1→𝐵 ↔ 𝐹:𝐴–1-1→𝐵)) | |
7 | 6 | spcegv 3596 | . . 3 ⊢ (𝐹 ∈ V → (𝐹:𝐴–1-1→𝐵 → ∃𝑓 𝑓:𝐴–1-1→𝐵)) |
8 | 5, 7 | syli 39 | . 2 ⊢ (𝐵 ∈ 𝐶 → (𝐹:𝐴–1-1→𝐵 → ∃𝑓 𝑓:𝐴–1-1→𝐵)) |
9 | brdomg 8995 | . 2 ⊢ (𝐵 ∈ 𝐶 → (𝐴 ≼ 𝐵 ↔ ∃𝑓 𝑓:𝐴–1-1→𝐵)) | |
10 | 8, 9 | sylibrd 259 | 1 ⊢ (𝐵 ∈ 𝐶 → (𝐹:𝐴–1-1→𝐵 → 𝐴 ≼ 𝐵)) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 ∃wex 1775 ∈ wcel 2105 Vcvv 3477 class class class wbr 5147 ⟶wf 6558 –1-1→wf1 6559 ≼ cdom 8981 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1791 ax-4 1805 ax-5 1907 ax-6 1964 ax-7 2004 ax-8 2107 ax-9 2115 ax-10 2138 ax-11 2154 ax-12 2174 ax-ext 2705 ax-rep 5284 ax-sep 5301 ax-nul 5311 ax-pr 5437 ax-un 7753 |
This theorem depends on definitions: df-bi 207 df-an 396 df-or 848 df-3an 1088 df-tru 1539 df-fal 1549 df-ex 1776 df-nf 1780 df-sb 2062 df-mo 2537 df-eu 2566 df-clab 2712 df-cleq 2726 df-clel 2813 df-nfc 2889 df-ne 2938 df-ral 3059 df-rex 3068 df-reu 3378 df-rab 3433 df-v 3479 df-sbc 3791 df-csb 3908 df-dif 3965 df-un 3967 df-in 3969 df-ss 3979 df-nul 4339 df-if 4531 df-sn 4631 df-pr 4633 df-op 4637 df-uni 4912 df-iun 4997 df-br 5148 df-opab 5210 df-mpt 5231 df-id 5582 df-xp 5694 df-rel 5695 df-cnv 5696 df-co 5697 df-dm 5698 df-rn 5699 df-res 5700 df-ima 5701 df-iota 6515 df-fun 6564 df-fn 6565 df-f 6566 df-f1 6567 df-fo 6568 df-f1o 6569 df-fv 6570 df-dom 8985 |
This theorem is referenced by: f1dom 9012 dom2d 9031 fseqen 10064 infpssrlem5 10344 hashf1 14492 vdwlem12 17025 2ndcdisj 23479 ovolicc2lem4 25568 basellem4 27141 usgriedgleord 29259 uspgredgleord 29263 |
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