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Theorem moeq3 1432
Description: "At most one" property of equality (split into 3 cases). (The first 2 hypotheses could be eliminated with longer proof.)
Hypotheses
Ref Expression
moeq3.1 |- B e. V
moeq3.2 |- C e. V
moeq3.3 |- -. (ph /\ ps)
Assertion
Ref Expression
moeq3 |- E*x((ph /\ x = A) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C))
Distinct variable group(s):   ph,x   ps,x   x,A   x,B   x,C

Proof of Theorem moeq3
StepHypRef Expression
1 cleq2 1110 . . . . . . 7 |- (y = A -> (x = y <-> x = A))
21anbi2d 468 . . . . . 6 |- (y = A -> ((ph /\ x = y) <-> (ph /\ x = A)))
3 pm4.2i 149 . . . . . 6 |- (y = A -> ((-. (ph \/ ps) /\ x = B) <-> (-. (ph \/ ps) /\ x = B)))
4 pm4.2i 149 . . . . . 6 |- (y = A -> ((ps /\ x = C) <-> (ps /\ x = C)))
52, 3, 4bi3ord 635 . . . . 5 |- (y = A -> (((ph /\ x = y) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C)) <-> ((ph /\ x = A) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C))))
65bieudv 1013 . . . 4 |- (y = A -> (E!x((ph /\ x = y) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C)) <-> E!x((ph /\ x = A) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C))))
7 visset 1350 . . . . 5 |- y e. V
8 moeq3.1 . . . . 5 |- B e. V
9 moeq3.2 . . . . 5 |- C e. V
10 moeq3.3 . . . . 5 |- -. (ph /\ ps)
117, 8, 9, 10eueq3 1430 . . . 4 |- E!x((ph /\ x = y) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C))
126, 11vtoclg 1383 . . 3 |- (A e. V -> E!x((ph /\ x = A) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C)))
13 eumo 1037 . . 3 |- (E!x((ph /\ x = A) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C)) -> E*x((ph /\ x = A) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C)))
1412, 13syl 12 . 2 |- (A e. V -> E*x((ph /\ x = A) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C)))
15 pm2.21 71 . . . . . . . . 9 |- (-. A e. V -> (A e. V -> x = y))
16 visset 1350 . . . . . . . . . 10 |- x e. V
17 eleq1 1149 . . . . . . . . . 10 |- (x = A -> (x e. V <-> A e. V))
1816, 17mpbii 168 . . . . . . . . 9 |- (x = A -> A e. V)
1915, 18syl5 22 . . . . . . . 8 |- (-. A e. V -> (x = A -> x = y))
2019anim2d 433 . . . . . . 7 |- (-. A e. V -> ((ph /\ x = A) -> (ph /\ x = y)))
2120orim1d 437 . . . . . 6 |- (-. A e. V -> (((ph /\ x = A) \/ ((-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C))) -> ((ph /\ x = y) \/ ((-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C)))))
22 3orass 584 . . . . . 6 |- (((ph /\ x = A) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C)) <-> ((ph /\ x = A) \/ ((-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C))))
23 3orass 584 . . . . . 6 |- (((ph /\ x = y) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C)) <-> ((ph /\ x = y) \/ ((-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C))))
2421, 22, 233imtr4g 426 . . . . 5 |- (-. A e. V -> (((ph /\ x = A) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C)) -> ((ph /\ x = y) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C))))
252419.21aiv 943 . . . 4 |- (-. A e. V -> A.x(((ph /\ x = A) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C)) -> ((ph /\ x = y) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C))))
26 euimmo 1045 . . . 4 |- (A.x(((ph /\ x = A) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C)) -> ((ph /\ x = y) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C))) -> (E!x((ph /\ x = y) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C)) -> E*x((ph /\ x = A) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C))))
2725, 26syl 12 . . 3 |- (-. A e. V -> (E!x((ph /\ x = y) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C)) -> E*x((ph /\ x = A) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C))))
2811, 27mpi 44 . 2 |- (-. A e. V -> E*x((ph /\ x = A) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C)))
2914, 28pm2.61i 110 1 |- E*x((ph /\ x = A) \/ (-. (ph \/ ps) /\ x = B) \/ (ps /\ x = C))
Colors of variables: wff set class
Syntax hints:  -. wn 1   -> wi 2   \/ wo 195   /\ wa 196   \/ w3o 580  A.wal 672   = weq 797  E!weu 1007  E*wmo 1008   = wceq 1091   e. wcel 1092  Vcvv 1348
This theorem is referenced by:  tz7.44lem1 2965
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-16 922  ax-17 925  ax-ext 1074
This theorem depends on definitions:  df-bi 128  df-or 197  df-an 198  df-3or 582  df-ex 679  df-sb 853  df-eu 1009  df-mo 1010  df-clab 1093  df-cleq 1097  df-clel 1099  df-v 1349
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