Theorem eninl 7437

Description: Equinumerosity of a set and its image under left injection. (Contributed by Jim Kingdon, 30-Jul-2023.)

Assertion

Ref	Expression
eninl	|- ( A e. V -> (inl " A ) ~~ A )

Proof of Theorem eninl

Step	Hyp	Ref	Expression
1		djulf1or 7396	. . . 4 |- (inl |` A ) : A -1-1-onto-> ( { (/) } X. A )
2		f1oeng 7043	. . . 4 |- ( ( A e. V /\ (inl |` A ) : A -1-1-onto-> ( { (/) } X. A ) ) -> A ~~ ( { (/) } X. A ) )
3	1, 2	mpan2 429	. . 3 |- ( A e. V -> A ~~ ( { (/) } X. A ) )
4		df-ima 4787	. . . 4 |- (inl " A ) = ran (inl |` A )
5		dff1o5 5648	. . . . . 6 |- ( (inl |` A ) : A -1-1-onto-> ( { (/) } X. A ) <-> ( (inl |` A ) : A -1-1-> ( { (/) } X. A ) /\ ran (inl |` A ) = ( { (/) } X. A ) ) )
6	1, 5	mpbi 145	. . . . 5 |- ( (inl |` A ) : A -1-1-> ( { (/) } X. A ) /\ ran (inl |` A ) = ( { (/) } X. A ) )
7	6	simpri 113	. . . 4 |- ran (inl |` A ) = ( { (/) } X. A )
8	4, 7	eqtri 2259	. . 3 |- (inl " A ) = ( { (/) } X. A )
9	3, 8	breqtrrdi 4172	. 2 |- ( A e. V -> A ~~ (inl " A ) )
10	9	ensymd 7070	1 |- ( A e. V -> (inl " A ) ~~ A )

This proof depends on syntax axioms:   -> wi 4   /\ wa 104   = wceq 1402   e. wcel 2209   (/)c0 3520   {csn 3709   class class class wbr 4130   X. cxp 4772   ran crn 4775   |` cres 4776   "cima 4777   -1-1->wf1 5374   -1-1-onto->wf1o 5376   ~~ cen 7020  inlcinl 7385

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-coll 4246  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-reu 2535  df-rab 2537  df-v 2823  df-sbc 3052  df-csb 3148  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-iun 4014  df-br 4131  df-opab 4193  df-mpt 4194  df-id 4438  df-xp 4780  df-rel 4781  df-cnv 4782  df-co 4783  df-dm 4784  df-rn 4785  df-res 4786  df-ima 4787  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-er 6807  df-en 7023  df-inl 7387

This theorem is used by:  endjudisj  7566  djuen  7567