Theorem domssr 7030

Description: If C is a superset of B and B dominates A, then C also dominates A. (Contributed by BTernaryTau, 7-Dec-2024.)

Assertion

Ref	Expression
domssr	|- ( ( C e. V /\ B C_ C /\ A ~<_ B ) -> A ~<_ C )

Proof of Theorem domssr

Dummy variable f is distinct from all other variables.

Step	Hyp	Ref	Expression
1		brdomi 6999	. . 3 |- ( A ~<_ B -> E. f f : A -1-1-> B )
2	1	3ad2ant3 1047	. 2 |- ( ( C e. V /\ B C_ C /\ A ~<_ B ) -> E. f f : A -1-1-> B )
3		simp2 1025	. . 3 |- ( ( C e. V /\ B C_ C /\ A ~<_ B ) -> B C_ C )
4		reldom 6993	. . . . 5 |- Rel ~<_
5	4	brrelex1i 4798	. . . 4 |- ( A ~<_ B -> A e. _V )
6	5	3ad2ant3 1047	. . 3 |- ( ( C e. V /\ B C_ C /\ A ~<_ B ) -> A e. _V )
7		simp1 1024	. . 3 |- ( ( C e. V /\ B C_ C /\ A ~<_ B ) -> C e. V )
8	3, 6, 7	jca32 310	. 2 |- ( ( C e. V /\ B C_ C /\ A ~<_ B ) -> ( B C_ C /\ ( A e. _V /\ C e. V ) ) )
9		f1ss 5584	. . . . 5 |- ( ( f : A -1-1-> B /\ B C_ C ) -> f : A -1-1-> C )
10		vex 2818	. . . . . . 7 |- f e. _V
11		f1dom4g 7005	. . . . . . 7 |- ( ( ( f e. _V /\ A e. _V /\ C e. V ) /\ f : A -1-1-> C ) -> A ~<_ C )
12	10, 11	mp3anl1 1368	. . . . . 6 |- ( ( ( A e. _V /\ C e. V ) /\ f : A -1-1-> C ) -> A ~<_ C )
13	12	ancoms 268	. . . . 5 |- ( ( f : A -1-1-> C /\ ( A e. _V /\ C e. V ) ) -> A ~<_ C )
14	9, 13	sylan 283	. . . 4 |- ( ( ( f : A -1-1-> B /\ B C_ C ) /\ ( A e. _V /\ C e. V ) ) -> A ~<_ C )
15	14	expl 378	. . 3 |- ( f : A -1-1-> B -> ( ( B C_ C /\ ( A e. _V /\ C e. V ) ) -> A ~<_ C ) )
16	15	exlimiv 1647	. 2 |- ( E. f f : A -1-1-> B -> ( ( B C_ C /\ ( A e. _V /\ C e. V ) ) -> A ~<_ C ) )
17	2, 8, 16	sylc 62	1 |- ( ( C e. V /\ B C_ C /\ A ~<_ B ) -> A ~<_ C )

Syntax hints:   -> wi 4   /\ wa 104   /\ w3a 1005   E.wex 1541   e. wcel 2205   _Vcvv 2815   C_ wss 3214   class class class wbr 4114   -1-1->wf1 5354   ~<_ cdom 6987

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-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-13 2207  ax-14 2208  ax-ext 2216  ax-sep 4233  ax-pow 4292  ax-pr 4327  ax-un 4559

This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-nf 1510  df-sb 1812  df-eu 2085  df-mo 2086  df-clab 2221  df-cleq 2227  df-clel 2230  df-nfc 2375  df-ral 2527  df-rex 2528  df-v 2817  df-un 3218  df-in 3220  df-ss 3227  df-pw 3676  df-sn 3700  df-pr 3701  df-op 3703  df-uni 3920  df-br 4115  df-opab 4177  df-xp 4760  df-rel 4761  df-cnv 4762  df-co 4763  df-dm 4764  df-rn 4765  df-fun 5359  df-fn 5360  df-f 5361  df-f1 5362  df-dom 6990

This theorem is referenced by:  rex2dom  7076