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Theorem fodju0 7337
Description: Lemma for fodjuomni 7339 and fodjumkv 7350. A condition which shows that 𝐴 is empty. (Contributed by Jim Kingdon, 27-Jul-2022.) (Revised by Jim Kingdon, 25-Mar-2023.)
Hypotheses
Ref Expression
fodjuf.fo (𝜑𝐹:𝑂onto→(𝐴𝐵))
fodjuf.p 𝑃 = (𝑦𝑂 ↦ if(∃𝑧𝐴 (𝐹𝑦) = (inl‘𝑧), ∅, 1o))
fodju0.1 (𝜑 → ∀𝑤𝑂 (𝑃𝑤) = 1o)
Assertion
Ref Expression
fodju0 (𝜑𝐴 = ∅)
Distinct variable groups:   𝜑,𝑦,𝑧   𝑦,𝑂,𝑧   𝑧,𝐴   𝑧,𝐵   𝑧,𝐹   𝑦,𝐴   𝑦,𝐹   𝑤,𝑂   𝑤,𝑃
Allowed substitution hints:   𝜑(𝑤)   𝐴(𝑤)   𝐵(𝑦,𝑤)   𝑃(𝑦,𝑧)   𝐹(𝑤)

Proof of Theorem fodju0
Dummy variables 𝑢 𝑣 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 fodjuf.fo . . . . 5 (𝜑𝐹:𝑂onto→(𝐴𝐵))
2 djulcl 7241 . . . . 5 (𝑢𝐴 → (inl‘𝑢) ∈ (𝐴𝐵))
3 foelrn 5888 . . . . 5 ((𝐹:𝑂onto→(𝐴𝐵) ∧ (inl‘𝑢) ∈ (𝐴𝐵)) → ∃𝑣𝑂 (inl‘𝑢) = (𝐹𝑣))
41, 2, 3syl2an 289 . . . 4 ((𝜑𝑢𝐴) → ∃𝑣𝑂 (inl‘𝑢) = (𝐹𝑣))
5 fodjuf.p . . . . . 6 𝑃 = (𝑦𝑂 ↦ if(∃𝑧𝐴 (𝐹𝑦) = (inl‘𝑧), ∅, 1o))
6 fveqeq2 5644 . . . . . . . 8 (𝑦 = 𝑣 → ((𝐹𝑦) = (inl‘𝑧) ↔ (𝐹𝑣) = (inl‘𝑧)))
76rexbidv 2531 . . . . . . 7 (𝑦 = 𝑣 → (∃𝑧𝐴 (𝐹𝑦) = (inl‘𝑧) ↔ ∃𝑧𝐴 (𝐹𝑣) = (inl‘𝑧)))
87ifbid 3625 . . . . . 6 (𝑦 = 𝑣 → if(∃𝑧𝐴 (𝐹𝑦) = (inl‘𝑧), ∅, 1o) = if(∃𝑧𝐴 (𝐹𝑣) = (inl‘𝑧), ∅, 1o))
9 simprl 529 . . . . . 6 (((𝜑𝑢𝐴) ∧ (𝑣𝑂 ∧ (inl‘𝑢) = (𝐹𝑣))) → 𝑣𝑂)
10 peano1 4690 . . . . . . . 8 ∅ ∈ ω
1110a1i 9 . . . . . . 7 (((𝜑𝑢𝐴) ∧ (𝑣𝑂 ∧ (inl‘𝑢) = (𝐹𝑣))) → ∅ ∈ ω)
12 1onn 6683 . . . . . . . 8 1o ∈ ω
1312a1i 9 . . . . . . 7 (((𝜑𝑢𝐴) ∧ (𝑣𝑂 ∧ (inl‘𝑢) = (𝐹𝑣))) → 1o ∈ ω)
141fodjuomnilemdc 7334 . . . . . . . 8 ((𝜑𝑣𝑂) → DECID𝑧𝐴 (𝐹𝑣) = (inl‘𝑧))
1514ad2ant2r 509 . . . . . . 7 (((𝜑𝑢𝐴) ∧ (𝑣𝑂 ∧ (inl‘𝑢) = (𝐹𝑣))) → DECID𝑧𝐴 (𝐹𝑣) = (inl‘𝑧))
1611, 13, 15ifcldcd 3641 . . . . . 6 (((𝜑𝑢𝐴) ∧ (𝑣𝑂 ∧ (inl‘𝑢) = (𝐹𝑣))) → if(∃𝑧𝐴 (𝐹𝑣) = (inl‘𝑧), ∅, 1o) ∈ ω)
175, 8, 9, 16fvmptd3 5736 . . . . 5 (((𝜑𝑢𝐴) ∧ (𝑣𝑂 ∧ (inl‘𝑢) = (𝐹𝑣))) → (𝑃𝑣) = if(∃𝑧𝐴 (𝐹𝑣) = (inl‘𝑧), ∅, 1o))
18 fveqeq2 5644 . . . . . 6 (𝑤 = 𝑣 → ((𝑃𝑤) = 1o ↔ (𝑃𝑣) = 1o))
19 fodju0.1 . . . . . . 7 (𝜑 → ∀𝑤𝑂 (𝑃𝑤) = 1o)
2019ad2antrr 488 . . . . . 6 (((𝜑𝑢𝐴) ∧ (𝑣𝑂 ∧ (inl‘𝑢) = (𝐹𝑣))) → ∀𝑤𝑂 (𝑃𝑤) = 1o)
2118, 20, 9rspcdva 2913 . . . . 5 (((𝜑𝑢𝐴) ∧ (𝑣𝑂 ∧ (inl‘𝑢) = (𝐹𝑣))) → (𝑃𝑣) = 1o)
22 simplr 528 . . . . . . 7 (((𝜑𝑢𝐴) ∧ (𝑣𝑂 ∧ (inl‘𝑢) = (𝐹𝑣))) → 𝑢𝐴)
23 simprr 531 . . . . . . . 8 (((𝜑𝑢𝐴) ∧ (𝑣𝑂 ∧ (inl‘𝑢) = (𝐹𝑣))) → (inl‘𝑢) = (𝐹𝑣))
2423eqcomd 2235 . . . . . . 7 (((𝜑𝑢𝐴) ∧ (𝑣𝑂 ∧ (inl‘𝑢) = (𝐹𝑣))) → (𝐹𝑣) = (inl‘𝑢))
25 fveq2 5635 . . . . . . . 8 (𝑧 = 𝑢 → (inl‘𝑧) = (inl‘𝑢))
2625rspceeqv 2926 . . . . . . 7 ((𝑢𝐴 ∧ (𝐹𝑣) = (inl‘𝑢)) → ∃𝑧𝐴 (𝐹𝑣) = (inl‘𝑧))
2722, 24, 26syl2anc 411 . . . . . 6 (((𝜑𝑢𝐴) ∧ (𝑣𝑂 ∧ (inl‘𝑢) = (𝐹𝑣))) → ∃𝑧𝐴 (𝐹𝑣) = (inl‘𝑧))
2827iftrued 3610 . . . . 5 (((𝜑𝑢𝐴) ∧ (𝑣𝑂 ∧ (inl‘𝑢) = (𝐹𝑣))) → if(∃𝑧𝐴 (𝐹𝑣) = (inl‘𝑧), ∅, 1o) = ∅)
2917, 21, 283eqtr3rd 2271 . . . 4 (((𝜑𝑢𝐴) ∧ (𝑣𝑂 ∧ (inl‘𝑢) = (𝐹𝑣))) → ∅ = 1o)
304, 29rexlimddv 2653 . . 3 ((𝜑𝑢𝐴) → ∅ = 1o)
31 1n0 6595 . . . . 5 1o ≠ ∅
3231nesymi 2446 . . . 4 ¬ ∅ = 1o
3332a1i 9 . . 3 ((𝜑𝑢𝐴) → ¬ ∅ = 1o)
3430, 33pm2.65da 665 . 2 (𝜑 → ¬ 𝑢𝐴)
3534eq0rdv 3537 1 (𝜑𝐴 = ∅)
Colors of variables: wff set class
Syntax hints:  ¬ wn 3  wi 4  wa 104  DECID wdc 839   = wceq 1395  wcel 2200  wral 2508  wrex 2509  c0 3492  ifcif 3603  cmpt 4148  ωcom 4686  ontowfo 5322  cfv 5324  1oc1o 6570  cdju 7227  inlcinl 7235
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 617  ax-in2 618  ax-io 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-13 2202  ax-14 2203  ax-ext 2211  ax-sep 4205  ax-nul 4213  ax-pow 4262  ax-pr 4297  ax-un 4528
This theorem depends on definitions:  df-bi 117  df-dc 840  df-3an 1004  df-tru 1398  df-fal 1401  df-nf 1507  df-sb 1809  df-eu 2080  df-mo 2081  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-ne 2401  df-ral 2513  df-rex 2514  df-v 2802  df-sbc 3030  df-csb 3126  df-dif 3200  df-un 3202  df-in 3204  df-ss 3211  df-nul 3493  df-if 3604  df-pw 3652  df-sn 3673  df-pr 3674  df-op 3676  df-uni 3892  df-int 3927  df-br 4087  df-opab 4149  df-mpt 4150  df-tr 4186  df-id 4388  df-iord 4461  df-on 4463  df-suc 4466  df-iom 4687  df-xp 4729  df-rel 4730  df-cnv 4731  df-co 4732  df-dm 4733  df-rn 4734  df-res 4735  df-ima 4736  df-iota 5284  df-fun 5326  df-fn 5327  df-f 5328  df-f1 5329  df-fo 5330  df-f1o 5331  df-fv 5332  df-1st 6298  df-2nd 6299  df-1o 6577  df-dju 7228  df-inl 7237  df-inr 7238
This theorem is referenced by:  fodjuomnilemres  7338  fodjumkvlemres  7349
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