ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  dom2lem GIF version

Theorem dom2lem 6419
Description: A mapping (first hypothesis) that is one-to-one (second hypothesis) implies its domain is dominated by its codomain. (Contributed by NM, 24-Jul-2004.)
Hypotheses
Ref Expression
dom2d.1 (𝜑 → (𝑥𝐴𝐶𝐵))
dom2d.2 (𝜑 → ((𝑥𝐴𝑦𝐴) → (𝐶 = 𝐷𝑥 = 𝑦)))
Assertion
Ref Expression
dom2lem (𝜑 → (𝑥𝐴𝐶):𝐴1-1𝐵)
Distinct variable groups:   𝑥,𝑦,𝐴   𝑥,𝐵,𝑦   𝑦,𝐶   𝑥,𝐷   𝜑,𝑥,𝑦
Allowed substitution hints:   𝐶(𝑥)   𝐷(𝑦)

Proof of Theorem dom2lem
StepHypRef Expression
1 dom2d.1 . . . 4 (𝜑 → (𝑥𝐴𝐶𝐵))
21ralrimiv 2439 . . 3 (𝜑 → ∀𝑥𝐴 𝐶𝐵)
3 eqid 2083 . . . 4 (𝑥𝐴𝐶) = (𝑥𝐴𝐶)
43fmpt 5394 . . 3 (∀𝑥𝐴 𝐶𝐵 ↔ (𝑥𝐴𝐶):𝐴𝐵)
52, 4sylib 120 . 2 (𝜑 → (𝑥𝐴𝐶):𝐴𝐵)
61imp 122 . . . . . . 7 ((𝜑𝑥𝐴) → 𝐶𝐵)
73fvmpt2 5331 . . . . . . . 8 ((𝑥𝐴𝐶𝐵) → ((𝑥𝐴𝐶)‘𝑥) = 𝐶)
87adantll 460 . . . . . . 7 (((𝜑𝑥𝐴) ∧ 𝐶𝐵) → ((𝑥𝐴𝐶)‘𝑥) = 𝐶)
96, 8mpdan 412 . . . . . 6 ((𝜑𝑥𝐴) → ((𝑥𝐴𝐶)‘𝑥) = 𝐶)
109adantrr 463 . . . . 5 ((𝜑 ∧ (𝑥𝐴𝑦𝐴)) → ((𝑥𝐴𝐶)‘𝑥) = 𝐶)
11 nfv 1462 . . . . . . . 8 𝑥(𝜑𝑦𝐴)
12 nffvmpt1 5261 . . . . . . . . 9 𝑥((𝑥𝐴𝐶)‘𝑦)
1312nfeq1 2232 . . . . . . . 8 𝑥((𝑥𝐴𝐶)‘𝑦) = 𝐷
1411, 13nfim 1505 . . . . . . 7 𝑥((𝜑𝑦𝐴) → ((𝑥𝐴𝐶)‘𝑦) = 𝐷)
15 eleq1 2145 . . . . . . . . . 10 (𝑥 = 𝑦 → (𝑥𝐴𝑦𝐴))
1615anbi2d 452 . . . . . . . . 9 (𝑥 = 𝑦 → ((𝜑𝑥𝐴) ↔ (𝜑𝑦𝐴)))
1716imbi1d 229 . . . . . . . 8 (𝑥 = 𝑦 → (((𝜑𝑥𝐴) → ((𝑥𝐴𝐶)‘𝑥) = 𝐶) ↔ ((𝜑𝑦𝐴) → ((𝑥𝐴𝐶)‘𝑥) = 𝐶)))
1815anbi1d 453 . . . . . . . . . . . 12 (𝑥 = 𝑦 → ((𝑥𝐴𝑦𝐴) ↔ (𝑦𝐴𝑦𝐴)))
19 anidm 388 . . . . . . . . . . . 12 ((𝑦𝐴𝑦𝐴) ↔ 𝑦𝐴)
2018, 19syl6bb 194 . . . . . . . . . . 11 (𝑥 = 𝑦 → ((𝑥𝐴𝑦𝐴) ↔ 𝑦𝐴))
2120anbi2d 452 . . . . . . . . . 10 (𝑥 = 𝑦 → ((𝜑 ∧ (𝑥𝐴𝑦𝐴)) ↔ (𝜑𝑦𝐴)))
22 fveq2 5253 . . . . . . . . . . . . 13 (𝑥 = 𝑦 → ((𝑥𝐴𝐶)‘𝑥) = ((𝑥𝐴𝐶)‘𝑦))
2322adantr 270 . . . . . . . . . . . 12 ((𝑥 = 𝑦 ∧ (𝜑 ∧ (𝑥𝐴𝑦𝐴))) → ((𝑥𝐴𝐶)‘𝑥) = ((𝑥𝐴𝐶)‘𝑦))
24 dom2d.2 . . . . . . . . . . . . . 14 (𝜑 → ((𝑥𝐴𝑦𝐴) → (𝐶 = 𝐷𝑥 = 𝑦)))
2524imp 122 . . . . . . . . . . . . 13 ((𝜑 ∧ (𝑥𝐴𝑦𝐴)) → (𝐶 = 𝐷𝑥 = 𝑦))
2625biimparc 293 . . . . . . . . . . . 12 ((𝑥 = 𝑦 ∧ (𝜑 ∧ (𝑥𝐴𝑦𝐴))) → 𝐶 = 𝐷)
2723, 26eqeq12d 2097 . . . . . . . . . . 11 ((𝑥 = 𝑦 ∧ (𝜑 ∧ (𝑥𝐴𝑦𝐴))) → (((𝑥𝐴𝐶)‘𝑥) = 𝐶 ↔ ((𝑥𝐴𝐶)‘𝑦) = 𝐷))
2827ex 113 . . . . . . . . . 10 (𝑥 = 𝑦 → ((𝜑 ∧ (𝑥𝐴𝑦𝐴)) → (((𝑥𝐴𝐶)‘𝑥) = 𝐶 ↔ ((𝑥𝐴𝐶)‘𝑦) = 𝐷)))
2921, 28sylbird 168 . . . . . . . . 9 (𝑥 = 𝑦 → ((𝜑𝑦𝐴) → (((𝑥𝐴𝐶)‘𝑥) = 𝐶 ↔ ((𝑥𝐴𝐶)‘𝑦) = 𝐷)))
3029pm5.74d 180 . . . . . . . 8 (𝑥 = 𝑦 → (((𝜑𝑦𝐴) → ((𝑥𝐴𝐶)‘𝑥) = 𝐶) ↔ ((𝜑𝑦𝐴) → ((𝑥𝐴𝐶)‘𝑦) = 𝐷)))
3117, 30bitrd 186 . . . . . . 7 (𝑥 = 𝑦 → (((𝜑𝑥𝐴) → ((𝑥𝐴𝐶)‘𝑥) = 𝐶) ↔ ((𝜑𝑦𝐴) → ((𝑥𝐴𝐶)‘𝑦) = 𝐷)))
3214, 31, 9chvar 1682 . . . . . 6 ((𝜑𝑦𝐴) → ((𝑥𝐴𝐶)‘𝑦) = 𝐷)
3332adantrl 462 . . . . 5 ((𝜑 ∧ (𝑥𝐴𝑦𝐴)) → ((𝑥𝐴𝐶)‘𝑦) = 𝐷)
3410, 33eqeq12d 2097 . . . 4 ((𝜑 ∧ (𝑥𝐴𝑦𝐴)) → (((𝑥𝐴𝐶)‘𝑥) = ((𝑥𝐴𝐶)‘𝑦) ↔ 𝐶 = 𝐷))
3525biimpd 142 . . . 4 ((𝜑 ∧ (𝑥𝐴𝑦𝐴)) → (𝐶 = 𝐷𝑥 = 𝑦))
3634, 35sylbid 148 . . 3 ((𝜑 ∧ (𝑥𝐴𝑦𝐴)) → (((𝑥𝐴𝐶)‘𝑥) = ((𝑥𝐴𝐶)‘𝑦) → 𝑥 = 𝑦))
3736ralrimivva 2449 . 2 (𝜑 → ∀𝑥𝐴𝑦𝐴 (((𝑥𝐴𝐶)‘𝑥) = ((𝑥𝐴𝐶)‘𝑦) → 𝑥 = 𝑦))
38 nfmpt1 3897 . . 3 𝑥(𝑥𝐴𝐶)
39 nfcv 2223 . . 3 𝑦(𝑥𝐴𝐶)
4038, 39dff13f 5489 . 2 ((𝑥𝐴𝐶):𝐴1-1𝐵 ↔ ((𝑥𝐴𝐶):𝐴𝐵 ∧ ∀𝑥𝐴𝑦𝐴 (((𝑥𝐴𝐶)‘𝑥) = ((𝑥𝐴𝐶)‘𝑦) → 𝑥 = 𝑦)))
415, 37, 40sylanbrc 408 1 (𝜑 → (𝑥𝐴𝐶):𝐴1-1𝐵)
Colors of variables: wff set class
Syntax hints:  wi 4  wa 102  wb 103   = wceq 1285  wcel 1434  wral 2353  cmpt 3865  wf 4965  1-1wf1 4966  cfv 4969
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-io 663  ax-5 1377  ax-7 1378  ax-gen 1379  ax-ie1 1423  ax-ie2 1424  ax-8 1436  ax-10 1437  ax-11 1438  ax-i12 1439  ax-bndl 1440  ax-4 1441  ax-14 1446  ax-17 1460  ax-i9 1464  ax-ial 1468  ax-i5r 1469  ax-ext 2065  ax-sep 3922  ax-pow 3974  ax-pr 4000
This theorem depends on definitions:  df-bi 115  df-3an 922  df-tru 1288  df-nf 1391  df-sb 1688  df-eu 1946  df-mo 1947  df-clab 2070  df-cleq 2076  df-clel 2079  df-nfc 2212  df-ral 2358  df-rex 2359  df-rab 2362  df-v 2614  df-sbc 2827  df-csb 2920  df-un 2988  df-in 2990  df-ss 2997  df-pw 3408  df-sn 3428  df-pr 3429  df-op 3431  df-uni 3628  df-br 3812  df-opab 3866  df-mpt 3867  df-id 4084  df-xp 4407  df-rel 4408  df-cnv 4409  df-co 4410  df-dm 4411  df-rn 4412  df-res 4413  df-ima 4414  df-iota 4934  df-fun 4971  df-fn 4972  df-f 4973  df-f1 4974  df-fv 4977
This theorem is referenced by:  dom2d  6420  dom3d  6421
  Copyright terms: Public domain W3C validator