Metamath Proof Explorer |
< Previous
Next >
Nearby theorems |
||
Mirrors > Home > MPE Home > Th. List > dff4 | Structured version Visualization version GIF version |
Description: Alternate definition of a mapping. (Contributed by NM, 20-Mar-2007.) |
Ref | Expression |
---|---|
dff4 | ⊢ (𝐹:𝐴⟶𝐵 ↔ (𝐹 ⊆ (𝐴 × 𝐵) ∧ ∀𝑥 ∈ 𝐴 ∃!𝑦 ∈ 𝐵 𝑥𝐹𝑦)) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | dff3 6976 | . 2 ⊢ (𝐹:𝐴⟶𝐵 ↔ (𝐹 ⊆ (𝐴 × 𝐵) ∧ ∀𝑥 ∈ 𝐴 ∃!𝑦 𝑥𝐹𝑦)) | |
2 | df-br 5075 | . . . . . . . 8 ⊢ (𝑥𝐹𝑦 ↔ 〈𝑥, 𝑦〉 ∈ 𝐹) | |
3 | ssel 3914 | . . . . . . . . 9 ⊢ (𝐹 ⊆ (𝐴 × 𝐵) → (〈𝑥, 𝑦〉 ∈ 𝐹 → 〈𝑥, 𝑦〉 ∈ (𝐴 × 𝐵))) | |
4 | opelxp2 5631 | . . . . . . . . 9 ⊢ (〈𝑥, 𝑦〉 ∈ (𝐴 × 𝐵) → 𝑦 ∈ 𝐵) | |
5 | 3, 4 | syl6 35 | . . . . . . . 8 ⊢ (𝐹 ⊆ (𝐴 × 𝐵) → (〈𝑥, 𝑦〉 ∈ 𝐹 → 𝑦 ∈ 𝐵)) |
6 | 2, 5 | syl5bi 241 | . . . . . . 7 ⊢ (𝐹 ⊆ (𝐴 × 𝐵) → (𝑥𝐹𝑦 → 𝑦 ∈ 𝐵)) |
7 | 6 | pm4.71rd 563 | . . . . . 6 ⊢ (𝐹 ⊆ (𝐴 × 𝐵) → (𝑥𝐹𝑦 ↔ (𝑦 ∈ 𝐵 ∧ 𝑥𝐹𝑦))) |
8 | 7 | eubidv 2586 | . . . . 5 ⊢ (𝐹 ⊆ (𝐴 × 𝐵) → (∃!𝑦 𝑥𝐹𝑦 ↔ ∃!𝑦(𝑦 ∈ 𝐵 ∧ 𝑥𝐹𝑦))) |
9 | df-reu 3072 | . . . . 5 ⊢ (∃!𝑦 ∈ 𝐵 𝑥𝐹𝑦 ↔ ∃!𝑦(𝑦 ∈ 𝐵 ∧ 𝑥𝐹𝑦)) | |
10 | 8, 9 | bitr4di 289 | . . . 4 ⊢ (𝐹 ⊆ (𝐴 × 𝐵) → (∃!𝑦 𝑥𝐹𝑦 ↔ ∃!𝑦 ∈ 𝐵 𝑥𝐹𝑦)) |
11 | 10 | ralbidv 3112 | . . 3 ⊢ (𝐹 ⊆ (𝐴 × 𝐵) → (∀𝑥 ∈ 𝐴 ∃!𝑦 𝑥𝐹𝑦 ↔ ∀𝑥 ∈ 𝐴 ∃!𝑦 ∈ 𝐵 𝑥𝐹𝑦)) |
12 | 11 | pm5.32i 575 | . 2 ⊢ ((𝐹 ⊆ (𝐴 × 𝐵) ∧ ∀𝑥 ∈ 𝐴 ∃!𝑦 𝑥𝐹𝑦) ↔ (𝐹 ⊆ (𝐴 × 𝐵) ∧ ∀𝑥 ∈ 𝐴 ∃!𝑦 ∈ 𝐵 𝑥𝐹𝑦)) |
13 | 1, 12 | bitri 274 | 1 ⊢ (𝐹:𝐴⟶𝐵 ↔ (𝐹 ⊆ (𝐴 × 𝐵) ∧ ∀𝑥 ∈ 𝐴 ∃!𝑦 ∈ 𝐵 𝑥𝐹𝑦)) |
Colors of variables: wff setvar class |
Syntax hints: ↔ wb 205 ∧ wa 396 ∈ wcel 2106 ∃!weu 2568 ∀wral 3064 ∃!wreu 3066 ⊆ wss 3887 〈cop 4567 class class class wbr 5074 × cxp 5587 ⟶wf 6429 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1798 ax-4 1812 ax-5 1913 ax-6 1971 ax-7 2011 ax-8 2108 ax-9 2116 ax-10 2137 ax-11 2154 ax-12 2171 ax-ext 2709 ax-sep 5223 ax-nul 5230 ax-pr 5352 |
This theorem depends on definitions: df-bi 206 df-an 397 df-or 845 df-3an 1088 df-tru 1542 df-fal 1552 df-ex 1783 df-nf 1787 df-sb 2068 df-mo 2540 df-eu 2569 df-clab 2716 df-cleq 2730 df-clel 2816 df-nfc 2889 df-ne 2944 df-ral 3069 df-rex 3070 df-reu 3072 df-rab 3073 df-v 3434 df-dif 3890 df-un 3892 df-in 3894 df-ss 3904 df-nul 4257 df-if 4460 df-sn 4562 df-pr 4564 df-op 4568 df-uni 4840 df-br 5075 df-opab 5137 df-id 5489 df-xp 5595 df-rel 5596 df-cnv 5597 df-co 5598 df-dm 5599 df-rn 5600 df-iota 6391 df-fun 6435 df-fn 6436 df-f 6437 df-fv 6441 |
This theorem is referenced by: exfo 6981 |
Copyright terms: Public domain | W3C validator |