Metamath Proof Explorer


Theorem infdjuabs

Description: Absorption law for addition to an infinite cardinal. (Contributed by NM, 30-Sep-2004) (Revised by Mario Carneiro, 29-Apr-2015)

Ref Expression
Assertion infdjuabs
|- ( ( A e. dom card /\ _om ~<_ A /\ B ~<_ A ) -> ( A |_| B ) ~~ A )

Proof

Step Hyp Ref Expression
1 simp3
 |-  ( ( A e. dom card /\ _om ~<_ A /\ B ~<_ A ) -> B ~<_ A )
2 reldom
 |-  Rel ~<_
3 2 brrelex2i
 |-  ( B ~<_ A -> A e. _V )
4 djudom2
 |-  ( ( B ~<_ A /\ A e. _V ) -> ( A |_| B ) ~<_ ( A |_| A ) )
5 1 3 4 syl2anc2
 |-  ( ( A e. dom card /\ _om ~<_ A /\ B ~<_ A ) -> ( A |_| B ) ~<_ ( A |_| A ) )
6 xp2dju
 |-  ( 2o X. A ) = ( A |_| A )
7 5 6 breqtrrdi
 |-  ( ( A e. dom card /\ _om ~<_ A /\ B ~<_ A ) -> ( A |_| B ) ~<_ ( 2o X. A ) )
8 simp1
 |-  ( ( A e. dom card /\ _om ~<_ A /\ B ~<_ A ) -> A e. dom card )
9 2onn
 |-  2o e. _om
10 nnsdom
 |-  ( 2o e. _om -> 2o ~< _om )
11 sdomdom
 |-  ( 2o ~< _om -> 2o ~<_ _om )
12 9 10 11 mp2b
 |-  2o ~<_ _om
13 simp2
 |-  ( ( A e. dom card /\ _om ~<_ A /\ B ~<_ A ) -> _om ~<_ A )
14 domtr
 |-  ( ( 2o ~<_ _om /\ _om ~<_ A ) -> 2o ~<_ A )
15 12 13 14 sylancr
 |-  ( ( A e. dom card /\ _om ~<_ A /\ B ~<_ A ) -> 2o ~<_ A )
16 xpdom1g
 |-  ( ( A e. dom card /\ 2o ~<_ A ) -> ( 2o X. A ) ~<_ ( A X. A ) )
17 8 15 16 syl2anc
 |-  ( ( A e. dom card /\ _om ~<_ A /\ B ~<_ A ) -> ( 2o X. A ) ~<_ ( A X. A ) )
18 domtr
 |-  ( ( ( A |_| B ) ~<_ ( 2o X. A ) /\ ( 2o X. A ) ~<_ ( A X. A ) ) -> ( A |_| B ) ~<_ ( A X. A ) )
19 7 17 18 syl2anc
 |-  ( ( A e. dom card /\ _om ~<_ A /\ B ~<_ A ) -> ( A |_| B ) ~<_ ( A X. A ) )
20 infxpidm2
 |-  ( ( A e. dom card /\ _om ~<_ A ) -> ( A X. A ) ~~ A )
21 20 3adant3
 |-  ( ( A e. dom card /\ _om ~<_ A /\ B ~<_ A ) -> ( A X. A ) ~~ A )
22 domentr
 |-  ( ( ( A |_| B ) ~<_ ( A X. A ) /\ ( A X. A ) ~~ A ) -> ( A |_| B ) ~<_ A )
23 19 21 22 syl2anc
 |-  ( ( A e. dom card /\ _om ~<_ A /\ B ~<_ A ) -> ( A |_| B ) ~<_ A )
24 2 brrelex1i
 |-  ( B ~<_ A -> B e. _V )
25 24 3ad2ant3
 |-  ( ( A e. dom card /\ _om ~<_ A /\ B ~<_ A ) -> B e. _V )
26 djudoml
 |-  ( ( A e. dom card /\ B e. _V ) -> A ~<_ ( A |_| B ) )
27 8 25 26 syl2anc
 |-  ( ( A e. dom card /\ _om ~<_ A /\ B ~<_ A ) -> A ~<_ ( A |_| B ) )
28 sbth
 |-  ( ( ( A |_| B ) ~<_ A /\ A ~<_ ( A |_| B ) ) -> ( A |_| B ) ~~ A )
29 23 27 28 syl2anc
 |-  ( ( A e. dom card /\ _om ~<_ A /\ B ~<_ A ) -> ( A |_| B ) ~~ A )