Theorem djuunr 7406

Description: The disjoint union of two classes is the union of the images of those two classes under right and left injection. (Contributed by Jim Kingdon, 22-Jun-2022.) (Proof shortened by BJ, 6-Jul-2022.)

Assertion

Ref	Expression
djuunr	|- ( ran (inl |` A ) u. ran (inr |` B ) ) = ( A ⊔ B )

Proof of Theorem djuunr

Step	Hyp	Ref	Expression
1		djulf1or 7396	. . . 4 |- (inl |` A ) : A -1-1-onto-> ( { (/) } X. A )
2		f1ofo 5646	. . . 4 |- ( (inl |` A ) : A -1-1-onto-> ( { (/) } X. A ) -> (inl |` A ) : A -onto-> ( { (/) } X. A ) )
3		forn 5618	. . . 4 |- ( (inl |` A ) : A -onto-> ( { (/) } X. A ) -> ran (inl |` A ) = ( { (/) } X. A ) )
4	1, 2, 3	mp2b 8	. . 3 |- ran (inl |` A ) = ( { (/) } X. A )
5		djurf1or 7397	. . . 4 |- (inr |` B ) : B -1-1-onto-> ( { 1o } X. B )
6		f1ofo 5646	. . . 4 |- ( (inr |` B ) : B -1-1-onto-> ( { 1o } X. B ) -> (inr |` B ) : B -onto-> ( { 1o } X. B ) )
7		forn 5618	. . . 4 |- ( (inr |` B ) : B -onto-> ( { 1o } X. B ) -> ran (inr |` B ) = ( { 1o } X. B ) )
8	5, 6, 7	mp2b 8	. . 3 |- ran (inr |` B ) = ( { 1o } X. B )
9	4, 8	uneq12i 3381	. 2 |- ( ran (inl |` A ) u. ran (inr |` B ) ) = ( ( { (/) } X. A ) u. ( { 1o } X. B ) )
10		df-dju 7378	. 2 |- ( A ⊔ B ) = ( ( { (/) } X. A ) u. ( { 1o } X. B ) )
11	9, 10	eqtr4i 2262	1 |- ( ran (inl |` A ) u. ran (inr |` B ) ) = ( A ⊔ B )

This proof depends on syntax axioms:   = wceq 1402   u. cun 3218   (/)c0 3520   {csn 3709   X. cxp 4772   ran crn 4775   |` cres 4776   -onto->wfo 5375   -1-1-onto->wf1o 5376   1oc1o 6680   ⊔ cdju 7377  inlcinl 7385  inrcinr 7386

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-sep 4249  ax-nul 4259  ax-pow 4311  ax-pr 4346  ax-un 4578

This proof depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ral 2533  df-rex 2534  df-v 2823  df-sbc 3052  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-nul 3521  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-br 4131  df-opab 4193  df-mpt 4194  df-tr 4230  df-id 4438  df-iord 4511  df-on 4513  df-suc 4516  df-xp 4780  df-rel 4781  df-cnv 4782  df-co 4783  df-dm 4784  df-rn 4785  df-res 4786  df-iota 5337  df-fun 5379  df-fn 5380  df-f 5381  df-f1 5382  df-fo 5383  df-f1o 5384  df-fv 5385  df-1st 6374  df-2nd 6375  df-1o 6687  df-dju 7378  df-inl 7387  df-inr 7388

This theorem is used by:  djuun  7407  eldju  7408  casedm  7426  djudm  7445