Theorem caseinj 6974

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

Step	Hyp	Ref	Expression
1		df-inl 6932	. . . . . . 7 ⊢ inl = (𝑦 ∈ V ↦ ⟨∅, 𝑦⟩)
2	1	funmpt2 5162	. . . . . 6 ⊢ Fun inl
3		funcnvcnv 5182	. . . . . 6 ⊢ (Fun inl → Fun ◡◡inl)
4	2, 3	ax-mp 5	. . . . 5 ⊢ Fun ◡◡inl
5		caseinj.r	. . . . 5 ⊢ (𝜑 → Fun ◡𝑅)
6		funco 5163	. . . . 5 ⊢ ((Fun ◡◡inl ∧ Fun ◡𝑅) → Fun (◡◡inl ∘ ◡𝑅))
7	4, 5, 6	sylancr 410	. . . 4 ⊢ (𝜑 → Fun (◡◡inl ∘ ◡𝑅))
8		cnvco 4724	. . . . 5 ⊢ ◡(𝑅 ∘ ◡inl) = (◡◡inl ∘ ◡𝑅)
9	8	funeqi 5144	. . . 4 ⊢ (Fun ◡(𝑅 ∘ ◡inl) ↔ Fun (◡◡inl ∘ ◡𝑅))
10	7, 9	sylibr 133	. . 3 ⊢ (𝜑 → Fun ◡(𝑅 ∘ ◡inl))
11		df-inr 6933	. . . . . . 7 ⊢ inr = (𝑥 ∈ V ↦ ⟨1o, 𝑥⟩)
12	11	funmpt2 5162	. . . . . 6 ⊢ Fun inr
13		funcnvcnv 5182	. . . . . 6 ⊢ (Fun inr → Fun ◡◡inr)
14	12, 13	ax-mp 5	. . . . 5 ⊢ Fun ◡◡inr
15		caseinj.s	. . . . 5 ⊢ (𝜑 → Fun ◡𝑆)
16		funco 5163	. . . . 5 ⊢ ((Fun ◡◡inr ∧ Fun ◡𝑆) → Fun (◡◡inr ∘ ◡𝑆))
17	14, 15, 16	sylancr 410	. . . 4 ⊢ (𝜑 → Fun (◡◡inr ∘ ◡𝑆))
18		cnvco 4724	. . . . 5 ⊢ ◡(𝑆 ∘ ◡inr) = (◡◡inr ∘ ◡𝑆)
19	18	funeqi 5144	. . . 4 ⊢ (Fun ◡(𝑆 ∘ ◡inr) ↔ Fun (◡◡inr ∘ ◡𝑆))
20	17, 19	sylibr 133	. . 3 ⊢ (𝜑 → Fun ◡(𝑆 ∘ ◡inr))
21		df-rn 4550	. . . . . . 7 ⊢ ran (𝑅 ∘ ◡inl) = dom ◡(𝑅 ∘ ◡inl)
22		rncoss 4809	. . . . . . 7 ⊢ ran (𝑅 ∘ ◡inl) ⊆ ran 𝑅
23	21, 22	eqsstrri 3130	. . . . . 6 ⊢ dom ◡(𝑅 ∘ ◡inl) ⊆ ran 𝑅
24		df-rn 4550	. . . . . . 7 ⊢ ran (𝑆 ∘ ◡inr) = dom ◡(𝑆 ∘ ◡inr)
25		rncoss 4809	. . . . . . 7 ⊢ ran (𝑆 ∘ ◡inr) ⊆ ran 𝑆
26	24, 25	eqsstrri 3130	. . . . . 6 ⊢ dom ◡(𝑆 ∘ ◡inr) ⊆ ran 𝑆
27		ss2in 3304	. . . . . 6 ⊢ ((dom ◡(𝑅 ∘ ◡inl) ⊆ ran 𝑅 ∧ dom ◡(𝑆 ∘ ◡inr) ⊆ ran 𝑆) → (dom ◡(𝑅 ∘ ◡inl) ∩ dom ◡(𝑆 ∘ ◡inr)) ⊆ (ran 𝑅 ∩ ran 𝑆))
28	23, 26, 27	mp2an 422	. . . . 5 ⊢ (dom ◡(𝑅 ∘ ◡inl) ∩ dom ◡(𝑆 ∘ ◡inr)) ⊆ (ran 𝑅 ∩ ran 𝑆)
29		caseinj.disj	. . . . 5 ⊢ (𝜑 → (ran 𝑅 ∩ ran 𝑆) = ∅)
30	28, 29	sseqtrid 3147	. . . 4 ⊢ (𝜑 → (dom ◡(𝑅 ∘ ◡inl) ∩ dom ◡(𝑆 ∘ ◡inr)) ⊆ ∅)
31		ss0 3403	. . . 4 ⊢ ((dom ◡(𝑅 ∘ ◡inl) ∩ dom ◡(𝑆 ∘ ◡inr)) ⊆ ∅ → (dom ◡(𝑅 ∘ ◡inl) ∩ dom ◡(𝑆 ∘ ◡inr)) = ∅)
32	30, 31	syl 14	. . 3 ⊢ (𝜑 → (dom ◡(𝑅 ∘ ◡inl) ∩ dom ◡(𝑆 ∘ ◡inr)) = ∅)
33		funun 5167	. . 3 ⊢ (((Fun ◡(𝑅 ∘ ◡inl) ∧ Fun ◡(𝑆 ∘ ◡inr)) ∧ (dom ◡(𝑅 ∘ ◡inl) ∩ dom ◡(𝑆 ∘ ◡inr)) = ∅) → Fun (◡(𝑅 ∘ ◡inl) ∪ ◡(𝑆 ∘ ◡inr)))
34	10, 20, 32, 33	syl21anc 1215	. 2 ⊢ (𝜑 → Fun (◡(𝑅 ∘ ◡inl) ∪ ◡(𝑆 ∘ ◡inr)))
35		df-case 6969	. . . . 5 ⊢ case(𝑅, 𝑆) = ((𝑅 ∘ ◡inl) ∪ (𝑆 ∘ ◡inr))
36	35	cnveqi 4714	. . . 4 ⊢ ◡case(𝑅, 𝑆) = ◡((𝑅 ∘ ◡inl) ∪ (𝑆 ∘ ◡inr))
37		cnvun 4944	. . . 4 ⊢ ◡((𝑅 ∘ ◡inl) ∪ (𝑆 ∘ ◡inr)) = (◡(𝑅 ∘ ◡inl) ∪ ◡(𝑆 ∘ ◡inr))
38	36, 37	eqtri 2160	. . 3 ⊢ ◡case(𝑅, 𝑆) = (◡(𝑅 ∘ ◡inl) ∪ ◡(𝑆 ∘ ◡inr))
39	38	funeqi 5144	. 2 ⊢ (Fun ◡case(𝑅, 𝑆) ↔ Fun (◡(𝑅 ∘ ◡inl) ∪ ◡(𝑆 ∘ ◡inr)))
40	34, 39	sylibr 133	1 ⊢ (𝜑 → Fun ◡case(𝑅, 𝑆))

Syntax hints:   → wi 4   = wceq 1331  Vcvv 2686   ∪ cun 3069   ∩ cin 3070   ⊆ wss 3071  ∅c0 3363  ⟨cop 3530  ^◡ccnv 4538  dom cdm 4539  ran crn 4540   ∘ ccom 4543  Fun wfun 5117  1_oc1o 6306  inlcinl 6930  inrcinr 6931  casecdjucase 6968

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 603  ax-in2 604  ax-io 698  ax-5 1423  ax-7 1424  ax-gen 1425  ax-ie1 1469  ax-ie2 1470  ax-8 1482  ax-10 1483  ax-11 1484  ax-i12 1485  ax-bndl 1486  ax-4 1487  ax-14 1492  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-i5r 1515  ax-ext 2121  ax-sep 4046  ax-pow 4098  ax-pr 4131

This theorem depends on definitions:  df-bi 116  df-3an 964  df-tru 1334  df-nf 1437  df-sb 1736  df-eu 2002  df-mo 2003  df-clab 2126  df-cleq 2132  df-clel 2135  df-nfc 2270  df-ral 2421  df-rex 2422  df-v 2688  df-dif 3073  df-un 3075  df-in 3077  df-ss 3084  df-nul 3364  df-pw 3512  df-sn 3533  df-pr 3534  df-op 3536  df-br 3930  df-opab 3990  df-mpt 3991  df-id 4215  df-xp 4545  df-rel 4546  df-cnv 4547  df-co 4548  df-dm 4549  df-rn 4550  df-fun 5125  df-inl 6932  df-inr 6933  df-case 6969

This theorem is referenced by:  casef1  6975