MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  nfixp Structured version   Visualization version   GIF version

Theorem nfixp 8484
Description: Bound-variable hypothesis builder for indexed Cartesian product. Usage of this theorem is discouraged because it depends on ax-13 2389. Use the weaker nfixpw 8483 when possible. (Contributed by Mario Carneiro, 15-Oct-2016.) (New usage is discouraged.)
Hypotheses
Ref Expression
nfixp.1 𝑦𝐴
nfixp.2 𝑦𝐵
Assertion
Ref Expression
nfixp 𝑦X𝑥𝐴 𝐵

Proof of Theorem nfixp
Dummy variable 𝑧 is distinct from all other variables.
StepHypRef Expression
1 df-ixp 8465 . 2 X𝑥𝐴 𝐵 = {𝑧 ∣ (𝑧 Fn {𝑥𝑥𝐴} ∧ ∀𝑥𝐴 (𝑧𝑥) ∈ 𝐵)}
2 nfcv 2980 . . . . 5 𝑦𝑧
3 nftru 1804 . . . . . . 7 𝑥
4 nfcvf 3010 . . . . . . . . 9 (¬ ∀𝑦 𝑦 = 𝑥𝑦𝑥)
54adantl 484 . . . . . . . 8 ((⊤ ∧ ¬ ∀𝑦 𝑦 = 𝑥) → 𝑦𝑥)
6 nfixp.1 . . . . . . . . 9 𝑦𝐴
76a1i 11 . . . . . . . 8 ((⊤ ∧ ¬ ∀𝑦 𝑦 = 𝑥) → 𝑦𝐴)
85, 7nfeld 2992 . . . . . . 7 ((⊤ ∧ ¬ ∀𝑦 𝑦 = 𝑥) → Ⅎ𝑦 𝑥𝐴)
93, 8nfabd2 3005 . . . . . 6 (⊤ → 𝑦{𝑥𝑥𝐴})
109mptru 1543 . . . . 5 𝑦{𝑥𝑥𝐴}
112, 10nffn 6455 . . . 4 𝑦 𝑧 Fn {𝑥𝑥𝐴}
12 df-ral 3146 . . . . 5 (∀𝑥𝐴 (𝑧𝑥) ∈ 𝐵 ↔ ∀𝑥(𝑥𝐴 → (𝑧𝑥) ∈ 𝐵))
132a1i 11 . . . . . . . . . 10 ((⊤ ∧ ¬ ∀𝑦 𝑦 = 𝑥) → 𝑦𝑧)
1413, 5nffvd 6685 . . . . . . . . 9 ((⊤ ∧ ¬ ∀𝑦 𝑦 = 𝑥) → 𝑦(𝑧𝑥))
15 nfixp.2 . . . . . . . . . 10 𝑦𝐵
1615a1i 11 . . . . . . . . 9 ((⊤ ∧ ¬ ∀𝑦 𝑦 = 𝑥) → 𝑦𝐵)
1714, 16nfeld 2992 . . . . . . . 8 ((⊤ ∧ ¬ ∀𝑦 𝑦 = 𝑥) → Ⅎ𝑦(𝑧𝑥) ∈ 𝐵)
188, 17nfimd 1894 . . . . . . 7 ((⊤ ∧ ¬ ∀𝑦 𝑦 = 𝑥) → Ⅎ𝑦(𝑥𝐴 → (𝑧𝑥) ∈ 𝐵))
193, 18nfald2 2466 . . . . . 6 (⊤ → Ⅎ𝑦𝑥(𝑥𝐴 → (𝑧𝑥) ∈ 𝐵))
2019mptru 1543 . . . . 5 𝑦𝑥(𝑥𝐴 → (𝑧𝑥) ∈ 𝐵)
2112, 20nfxfr 1852 . . . 4 𝑦𝑥𝐴 (𝑧𝑥) ∈ 𝐵
2211, 21nfan 1899 . . 3 𝑦(𝑧 Fn {𝑥𝑥𝐴} ∧ ∀𝑥𝐴 (𝑧𝑥) ∈ 𝐵)
2322nfab 2987 . 2 𝑦{𝑧 ∣ (𝑧 Fn {𝑥𝑥𝐴} ∧ ∀𝑥𝐴 (𝑧𝑥) ∈ 𝐵)}
241, 23nfcxfr 2978 1 𝑦X𝑥𝐴 𝐵
Colors of variables: wff setvar class
Syntax hints:  ¬ wn 3  wi 4  wa 398  wal 1534  wtru 1537  wnf 1783  wcel 2113  {cab 2802  wnfc 2964  wral 3141   Fn wfn 6353  cfv 6358  Xcixp 8464
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1969  ax-7 2014  ax-8 2115  ax-9 2123  ax-10 2144  ax-11 2160  ax-12 2176  ax-13 2389  ax-ext 2796
This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-3an 1085  df-tru 1539  df-ex 1780  df-nf 1784  df-sb 2069  df-clab 2803  df-cleq 2817  df-clel 2896  df-nfc 2966  df-ral 3146  df-rex 3147  df-rab 3150  df-v 3499  df-dif 3942  df-un 3944  df-in 3946  df-ss 3955  df-nul 4295  df-if 4471  df-sn 4571  df-pr 4573  df-op 4577  df-uni 4842  df-br 5070  df-opab 5132  df-rel 5565  df-cnv 5566  df-co 5567  df-dm 5568  df-iota 6317  df-fun 6360  df-fn 6361  df-fv 6366  df-ixp 8465
This theorem is referenced by: (None)
  Copyright terms: Public domain W3C validator