Theorem casedm 7214

Description: The domain of the "case" construction is the disjoint union of the domains. TODO (although less important): ⊢ ran case(𝐹, 𝐺) = (ran 𝐹 ∪ ran 𝐺). (Contributed by BJ, 10-Jul-2022.)

Assertion

Ref	Expression
casedm	⊢ dom case(𝐹, 𝐺) = (dom 𝐹 ⊔ dom 𝐺)

Proof of Theorem casedm

Step	Hyp	Ref	Expression
1		df-case 7212	. . 3 ⊢ case(𝐹, 𝐺) = ((𝐹 ∘ ◡inl) ∪ (𝐺 ∘ ◡inr))
2	1	dmeqi 4898	. 2 ⊢ dom case(𝐹, 𝐺) = dom ((𝐹 ∘ ◡inl) ∪ (𝐺 ∘ ◡inr))
3		dmun 4904	. 2 ⊢ dom ((𝐹 ∘ ◡inl) ∪ (𝐺 ∘ ◡inr)) = (dom (𝐹 ∘ ◡inl) ∪ dom (𝐺 ∘ ◡inr))
4		dmco 5210	. . . . 5 ⊢ dom (𝐹 ∘ ◡inl) = (◡◡inl “ dom 𝐹)
5		imacnvcnv 5166	. . . . 5 ⊢ (◡◡inl “ dom 𝐹) = (inl “ dom 𝐹)
6		df-ima 4706	. . . . 5 ⊢ (inl “ dom 𝐹) = ran (inl ↾ dom 𝐹)
7	4, 5, 6	3eqtri 2232	. . . 4 ⊢ dom (𝐹 ∘ ◡inl) = ran (inl ↾ dom 𝐹)
8		dmco 5210	. . . . 5 ⊢ dom (𝐺 ∘ ◡inr) = (◡◡inr “ dom 𝐺)
9		imacnvcnv 5166	. . . . 5 ⊢ (◡◡inr “ dom 𝐺) = (inr “ dom 𝐺)
10		df-ima 4706	. . . . 5 ⊢ (inr “ dom 𝐺) = ran (inr ↾ dom 𝐺)
11	8, 9, 10	3eqtri 2232	. . . 4 ⊢ dom (𝐺 ∘ ◡inr) = ran (inr ↾ dom 𝐺)
12	7, 11	uneq12i 3333	. . 3 ⊢ (dom (𝐹 ∘ ◡inl) ∪ dom (𝐺 ∘ ◡inr)) = (ran (inl ↾ dom 𝐹) ∪ ran (inr ↾ dom 𝐺))
13		djuunr 7194	. . 3 ⊢ (ran (inl ↾ dom 𝐹) ∪ ran (inr ↾ dom 𝐺)) = (dom 𝐹 ⊔ dom 𝐺)
14	12, 13	eqtri 2228	. 2 ⊢ (dom (𝐹 ∘ ◡inl) ∪ dom (𝐺 ∘ ◡inr)) = (dom 𝐹 ⊔ dom 𝐺)
15	2, 3, 14	3eqtri 2232	1 ⊢ dom case(𝐹, 𝐺) = (dom 𝐹 ⊔ dom 𝐺)

Syntax hints:   = wceq 1373   ∪ cun 3172  ^◡ccnv 4692  dom cdm 4693  ran crn 4694   ↾ cres 4695   “ cima 4696   ∘ ccom 4697   ⊔ cdju 7165  inlcinl 7173  inrcinr 7174  casecdjucase 7211

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 615  ax-in2 616  ax-io 711  ax-5 1471  ax-7 1472  ax-gen 1473  ax-ie1 1517  ax-ie2 1518  ax-8 1528  ax-10 1529  ax-11 1530  ax-i12 1531  ax-bndl 1533  ax-4 1534  ax-17 1550  ax-i9 1554  ax-ial 1558  ax-i5r 1559  ax-13 2180  ax-14 2181  ax-ext 2189  ax-sep 4178  ax-nul 4186  ax-pow 4234  ax-pr 4269  ax-un 4498

This theorem depends on definitions:  df-bi 117  df-3an 983  df-tru 1376  df-nf 1485  df-sb 1787  df-eu 2058  df-mo 2059  df-clab 2194  df-cleq 2200  df-clel 2203  df-nfc 2339  df-ral 2491  df-rex 2492  df-v 2778  df-sbc 3006  df-dif 3176  df-un 3178  df-in 3180  df-ss 3187  df-nul 3469  df-pw 3628  df-sn 3649  df-pr 3650  df-op 3652  df-uni 3865  df-br 4060  df-opab 4122  df-mpt 4123  df-tr 4159  df-id 4358  df-iord 4431  df-on 4433  df-suc 4436  df-xp 4699  df-rel 4700  df-cnv 4701  df-co 4702  df-dm 4703  df-rn 4704  df-res 4705  df-ima 4706  df-iota 5251  df-fun 5292  df-fn 5293  df-f 5294  df-f1 5295  df-fo 5296  df-f1o 5297  df-fv 5298  df-1st 6249  df-2nd 6250  df-1o 6525  df-dju 7166  df-inl 7175  df-inr 7176  df-case 7212

This theorem is referenced by:  casef  7216