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Mirrors > Home > NFE Home > Th. List > f1funfun | GIF version |
Description: Two ways to express that a set A is one-to-one. Each side is equivalent to Definition 6.4(3) of [TakeutiZaring] p. 24, who use the notation "Un2 (A)" for one-to-one. We do not introduce a separate notation since we rarely use it. (Contributed by set.mm contributors, 13-Aug-2004.) (Revised by Scott Fenton, 18-Apr-2021.) |
Ref | Expression |
---|---|
f1funfun | ⊢ (A:dom A–1-1→V ↔ (Fun ◡A ∧ Fun A)) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-f1 4792 | . 2 ⊢ (A:dom A–1-1→V ↔ (A:dom A–→V ∧ Fun ◡A)) | |
2 | ancom 437 | . 2 ⊢ ((A:dom A–→V ∧ Fun ◡A) ↔ (Fun ◡A ∧ A:dom A–→V)) | |
3 | ssv 3291 | . . . . 5 ⊢ ran A ⊆ V | |
4 | df-f 4791 | . . . . 5 ⊢ (A:dom A–→V ↔ (A Fn dom A ∧ ran A ⊆ V)) | |
5 | 3, 4 | mpbiran2 885 | . . . 4 ⊢ (A:dom A–→V ↔ A Fn dom A) |
6 | funfn 5136 | . . . 4 ⊢ (Fun A ↔ A Fn dom A) | |
7 | 5, 6 | bitr4i 243 | . . 3 ⊢ (A:dom A–→V ↔ Fun A) |
8 | 7 | anbi2i 675 | . 2 ⊢ ((Fun ◡A ∧ A:dom A–→V) ↔ (Fun ◡A ∧ Fun A)) |
9 | 1, 2, 8 | 3bitri 262 | 1 ⊢ (A:dom A–1-1→V ↔ (Fun ◡A ∧ Fun A)) |
Colors of variables: wff setvar class |
Syntax hints: ↔ wb 176 ∧ wa 358 Vcvv 2859 ⊆ wss 3257 ◡ccnv 4771 dom cdm 4772 ran crn 4773 Fun wfun 4775 Fn wfn 4776 –→wf 4777 –1-1→wf1 4778 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1546 ax-5 1557 ax-17 1616 ax-9 1654 ax-8 1675 ax-6 1729 ax-7 1734 ax-11 1746 ax-12 1925 ax-ext 2334 |
This theorem depends on definitions: df-bi 177 df-or 359 df-an 360 df-nan 1288 df-tru 1319 df-ex 1542 df-nf 1545 df-sb 1649 df-clab 2340 df-cleq 2346 df-clel 2349 df-nfc 2478 df-v 2861 df-nin 3211 df-compl 3212 df-in 3213 df-ss 3259 df-fn 4790 df-f 4791 df-f1 4792 |
This theorem is referenced by: (None) |
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