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Theorem cdadom1 3727
Description: Ordering law for cardinal addition. Exercise 4.56(f) of [Mendelson] p. 258.
Hypotheses
Ref Expression
cdacomen.1 |- A e. V
cdacomen.2 |- B e. V
cdaassen.3 |- C e. V
Assertion
Ref Expression
cdadom1 |- (A ~<_ B -> (A +c C) ~<_ (B +c C))

Proof of Theorem cdadom1
StepHypRef Expression
1 cdacomen.1 . . . . 5 |- A e. V
2 0ex 1745 . . . . . 6 |- (/) e. V
31, 2xpsnen 3339 . . . . 5 |- (A X. {(/)}) ~~ A
4 domen1 3377 . . . . 5 |- ((A e. V /\ (A X. {(/)}) ~~ A) -> ((A X. {(/)}) ~<_ (B X. {(/)}) <-> A ~<_ (B X. {(/)})))
51, 3, 4mp2an 520 . . . 4 |- ((A X. {(/)}) ~<_ (B X. {(/)}) <-> A ~<_ (B X. {(/)}))
6 cdacomen.2 . . . . 5 |- B e. V
76, 2xpsnen 3339 . . . . 5 |- (B X. {(/)}) ~~ B
8 domen2 3378 . . . . 5 |- ((B e. V /\ (B X. {(/)}) ~~ B) -> (A ~<_ (B X. {(/)}) <-> A ~<_ B))
96, 7, 8mp2an 520 . . . 4 |- (A ~<_ (B X. {(/)}) <-> A ~<_ B)
105, 9bitr 151 . . 3 |- ((A X. {(/)}) ~<_ (B X. {(/)}) <-> A ~<_ B)
11 cdaassen.3 . . . . . 6 |- C e. V
12 snex 1859 . . . . . 6 |- {1o} e. V
1311, 12xpex 2488 . . . . 5 |- (C X. {1o}) e. V
14 domrefg 3297 . . . . 5 |- ((C X. {1o}) e. V -> (C X. {1o}) ~<_ (C X. {1o}))
1513, 14ax-mp 6 . . . 4 |- (C X. {1o}) ~<_ (C X. {1o})
16 0ne1oOLD 3113 . . . . . 6 |- -. (/) = 1o
17 xpsndisj 2655 . . . . . 6 |- (-. (/) = 1o -> ((B X. {(/)}) i^i (C X. {1o})) = (/))
1816, 17ax-mp 6 . . . . 5 |- ((B X. {(/)}) i^i (C X. {1o})) = (/)
19 p0ex 1885 . . . . . . 7 |- {(/)} e. V
206, 19xpex 2488 . . . . . 6 |- (B X. {(/)}) e. V
2120, 13, 13undom 3342 . . . . 5 |- ((((A X. {(/)}) ~<_ (B X. {(/)}) /\ (C X. {1o}) ~<_ (C X. {1o})) /\ ((B X. {(/)}) i^i (C X. {1o})) = (/)) -> ((A X. {(/)}) u. (C X. {1o})) ~<_ ((B X. {(/)}) u. (C X. {1o})))
2218, 21mpan2 519 . . . 4 |- (((A X. {(/)}) ~<_ (B X. {(/)}) /\ (C X. {1o}) ~<_ (C X. {1o})) -> ((A X. {(/)}) u. (C X. {1o})) ~<_ ((B X. {(/)}) u. (C X. {1o})))
2315, 22mpan2 519 . . 3 |- ((A X. {(/)}) ~<_ (B X. {(/)}) -> ((A X. {(/)}) u. (C X. {1o})) ~<_ ((B X. {(/)}) u. (C X. {1o})))
2410, 23sylbir 176 . 2 |- (A ~<_ B -> ((A X. {(/)}) u. (C X. {1o})) ~<_ ((B X. {(/)}) u. (C X. {1o})))
251, 11cdaval 3717 . 2 |- (A +c C) = ((A X. {(/)}) u. (C X. {1o}))
266, 11cdaval 3717 . 2 |- (B +c C) = ((B X. {(/)}) u. (C X. {1o}))
2724, 25, 263brtr4g 2088 1 |- (A ~<_ B -> (A +c C) ~<_ (B +c C))
Colors of variables: wff set class
Syntax hints:  -. wn 1   -> wi 2   <-> wb 127   /\ wa 196   = wceq 1091   e. wcel 1092  Vcvv 1348   u. cun 1485   i^i cin 1486  (/)c0 1707  {csn 1808   class class class wbr 2054   X. cxp 2408  (class class class)co 3001  1oc1o 3099   ~~ cen 3271   ~<_ cdom 3272   +c ccda 3714
This theorem is referenced by:  cdadom2 3728  infdif 4948
This theorem was proved from axioms:  ax-1 3  ax-2 4  ax-3 5  ax-mp 6  ax-4 673  ax-5 674  ax-6 675  ax-7 676  ax-gen 677  ax-8 798  ax-9 799  ax-10 800  ax-11 801  ax-12 802  ax-13 804  ax-14 805  ax-16 922  ax-17 925  ax-ext 1074  ax-rep 1075  ax-un 1076  ax-pow 1077
This theorem depends on definitions:  df-bi 128  df-or 197  df-an 198  df-3an 583  df-ex 679  df-sb 853  df-eu 1009  df-mo 1010  df-clab 1093  df-cleq 1097  df-clel 1099  df-ral 1205  df-rex 1206  df-v 1349  df-dif 1489  df-un 1490  df-in 1491  df-ss 1492  df-nul 1708  df-pw 1799  df-sn 1811  df-pr 1812  df-op 1815  df-uni 1920  df-int 1966  df-br 2063  df-opab 2098  df-id 2125  df-suc 2205  df-xp 2424  df-rel 2425  df-cnv 2426  df-co 2427  df-dm 2428  df-rn 2429  df-res 2430  df-ima 2431  df-fun 2432  df-fn 2433  df-f 2434  df-f1 2435  df-fo 2436  df-f1o 2437  df-fv 2438  df-opr 3003  df-oprab 3004  df-1o 3104  df-er 3200  df-en 3274  df-dom 3275  df-cda 3715
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