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Theorem caseinj 7066
Description: The "case" construction of two injective relations with disjoint ranges is an injective relation. (Contributed by BJ, 10-Jul-2022.)
Hypotheses
Ref Expression
caseinj.r (𝜑 → Fun 𝑅)
caseinj.s (𝜑 → Fun 𝑆)
caseinj.disj (𝜑 → (ran 𝑅 ∩ ran 𝑆) = ∅)
Assertion
Ref Expression
caseinj (𝜑 → Fun case(𝑅, 𝑆))

Proof of Theorem caseinj
StepHypRef Expression
1 df-inl 7024 . . . . . . 7 inl = (𝑦 ∈ V ↦ ⟨∅, 𝑦⟩)
21funmpt2 5237 . . . . . 6 Fun inl
3 funcnvcnv 5257 . . . . . 6 (Fun inl → Fun inl)
42, 3ax-mp 5 . . . . 5 Fun inl
5 caseinj.r . . . . 5 (𝜑 → Fun 𝑅)
6 funco 5238 . . . . 5 ((Fun inl ∧ Fun 𝑅) → Fun (inl ∘ 𝑅))
74, 5, 6sylancr 412 . . . 4 (𝜑 → Fun (inl ∘ 𝑅))
8 cnvco 4796 . . . . 5 (𝑅inl) = (inl ∘ 𝑅)
98funeqi 5219 . . . 4 (Fun (𝑅inl) ↔ Fun (inl ∘ 𝑅))
107, 9sylibr 133 . . 3 (𝜑 → Fun (𝑅inl))
11 df-inr 7025 . . . . . . 7 inr = (𝑥 ∈ V ↦ ⟨1o, 𝑥⟩)
1211funmpt2 5237 . . . . . 6 Fun inr
13 funcnvcnv 5257 . . . . . 6 (Fun inr → Fun inr)
1412, 13ax-mp 5 . . . . 5 Fun inr
15 caseinj.s . . . . 5 (𝜑 → Fun 𝑆)
16 funco 5238 . . . . 5 ((Fun inr ∧ Fun 𝑆) → Fun (inr ∘ 𝑆))
1714, 15, 16sylancr 412 . . . 4 (𝜑 → Fun (inr ∘ 𝑆))
18 cnvco 4796 . . . . 5 (𝑆inr) = (inr ∘ 𝑆)
1918funeqi 5219 . . . 4 (Fun (𝑆inr) ↔ Fun (inr ∘ 𝑆))
2017, 19sylibr 133 . . 3 (𝜑 → Fun (𝑆inr))
21 df-rn 4622 . . . . . . 7 ran (𝑅inl) = dom (𝑅inl)
22 rncoss 4881 . . . . . . 7 ran (𝑅inl) ⊆ ran 𝑅
2321, 22eqsstrri 3180 . . . . . 6 dom (𝑅inl) ⊆ ran 𝑅
24 df-rn 4622 . . . . . . 7 ran (𝑆inr) = dom (𝑆inr)
25 rncoss 4881 . . . . . . 7 ran (𝑆inr) ⊆ ran 𝑆
2624, 25eqsstrri 3180 . . . . . 6 dom (𝑆inr) ⊆ ran 𝑆
27 ss2in 3355 . . . . . 6 ((dom (𝑅inl) ⊆ ran 𝑅 ∧ dom (𝑆inr) ⊆ ran 𝑆) → (dom (𝑅inl) ∩ dom (𝑆inr)) ⊆ (ran 𝑅 ∩ ran 𝑆))
2823, 26, 27mp2an 424 . . . . 5 (dom (𝑅inl) ∩ dom (𝑆inr)) ⊆ (ran 𝑅 ∩ ran 𝑆)
29 caseinj.disj . . . . 5 (𝜑 → (ran 𝑅 ∩ ran 𝑆) = ∅)
3028, 29sseqtrid 3197 . . . 4 (𝜑 → (dom (𝑅inl) ∩ dom (𝑆inr)) ⊆ ∅)
31 ss0 3455 . . . 4 ((dom (𝑅inl) ∩ dom (𝑆inr)) ⊆ ∅ → (dom (𝑅inl) ∩ dom (𝑆inr)) = ∅)
3230, 31syl 14 . . 3 (𝜑 → (dom (𝑅inl) ∩ dom (𝑆inr)) = ∅)
33 funun 5242 . . 3 (((Fun (𝑅inl) ∧ Fun (𝑆inr)) ∧ (dom (𝑅inl) ∩ dom (𝑆inr)) = ∅) → Fun ((𝑅inl) ∪ (𝑆inr)))
3410, 20, 32, 33syl21anc 1232 . 2 (𝜑 → Fun ((𝑅inl) ∪ (𝑆inr)))
35 df-case 7061 . . . . 5 case(𝑅, 𝑆) = ((𝑅inl) ∪ (𝑆inr))
3635cnveqi 4786 . . . 4 case(𝑅, 𝑆) = ((𝑅inl) ∪ (𝑆inr))
37 cnvun 5016 . . . 4 ((𝑅inl) ∪ (𝑆inr)) = ((𝑅inl) ∪ (𝑆inr))
3836, 37eqtri 2191 . . 3 case(𝑅, 𝑆) = ((𝑅inl) ∪ (𝑆inr))
3938funeqi 5219 . 2 (Fun case(𝑅, 𝑆) ↔ Fun ((𝑅inl) ∪ (𝑆inr)))
4034, 39sylibr 133 1 (𝜑 → Fun case(𝑅, 𝑆))
Colors of variables: wff set class
Syntax hints:  wi 4   = wceq 1348  Vcvv 2730  cun 3119  cin 3120  wss 3121  c0 3414  cop 3586  ccnv 4610  dom cdm 4611  ran crn 4612  ccom 4615  Fun wfun 5192  1oc1o 6388  inlcinl 7022  inrcinr 7023  casecdjucase 7060
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 609  ax-in2 610  ax-io 704  ax-5 1440  ax-7 1441  ax-gen 1442  ax-ie1 1486  ax-ie2 1487  ax-8 1497  ax-10 1498  ax-11 1499  ax-i12 1500  ax-bndl 1502  ax-4 1503  ax-17 1519  ax-i9 1523  ax-ial 1527  ax-i5r 1528  ax-14 2144  ax-ext 2152  ax-sep 4107  ax-pow 4160  ax-pr 4194
This theorem depends on definitions:  df-bi 116  df-3an 975  df-tru 1351  df-nf 1454  df-sb 1756  df-eu 2022  df-mo 2023  df-clab 2157  df-cleq 2163  df-clel 2166  df-nfc 2301  df-ral 2453  df-rex 2454  df-v 2732  df-dif 3123  df-un 3125  df-in 3127  df-ss 3134  df-nul 3415  df-pw 3568  df-sn 3589  df-pr 3590  df-op 3592  df-br 3990  df-opab 4051  df-mpt 4052  df-id 4278  df-xp 4617  df-rel 4618  df-cnv 4619  df-co 4620  df-dm 4621  df-rn 4622  df-fun 5200  df-inl 7024  df-inr 7025  df-case 7061
This theorem is referenced by:  casef1  7067
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