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Theorem ghomgrpilem2 10381
Description: Lemma for ghomgrpi 10382.
Hypotheses
Ref Expression
ghomgrpilem1.1 |- G e. Grp
ghomgrpilem1.2 |- H e. Grp
ghomgrpilem1.3 |- F e. (G GrpHom H)
ghomgrpilem1.4 |- X = ran G
ghomgrpilem1.5 |- U = (Id` G)
ghomgrpilem1.6 |- N = (inv` G)
ghomgrpilem1.7 |- W = ran H
ghomgrpilem1.8 |- T = (Id` H)
ghomgrpilem1.9 |- M = (inv` H)
ghomgrpilem1.10 |- Z = ran F
ghomgrpilem1.11 |- S = (H |` (Z X. Z))
Assertion
Ref Expression
ghomgrpilem2 |- S e. (SubGrp` H)

Proof of Theorem ghomgrpilem2
StepHypRef Expression
1 ghomgrpilem1.2 . 2 |- H e. Grp
2 ghomgrpilem1.7 . 2 |- W = ran H
3 ghomgrpilem1.8 . 2 |- T = (Id` H)
4 ghomgrpilem1.9 . 2 |- M = (inv` H)
5 ghomgrpilem1.10 . . 3 |- Z = ran F
6 ghomgrpilem1.3 . . . . . 6 |- F e. (G GrpHom H)
7 ghomgrpilem1.1 . . . . . . 7 |- G e. Grp
8 ghomgrpilem1.4 . . . . . . . 8 |- X = ran G
98, 2elghom 10379 . . . . . . 7 |- ((G e. Grp /\ H e. Grp) -> (F e. (G GrpHom H) <-> (F:X-->W /\ A.x e. X A.y e. X ((F` x)H(F` y)) = (F` (xGy)))))
107, 1, 9mp2an 699 . . . . . 6 |- (F e. (G GrpHom H) <-> (F:X-->W /\ A.x e. X A.y e. X ((F` x)H(F` y)) = (F` (xGy))))
116, 10mpbi 189 . . . . 5 |- (F:X-->W /\ A.x e. X A.y e. X ((F` x)H(F` y)) = (F` (xGy)))
1211pm3.26i 320 . . . 4 |- F:X-->W
13 frn 3639 . . . 4 |- (F:X-->W -> ran F (_ W)
1412, 13ax-mp 7 . . 3 |- ran F (_ W
155, 14eqsstr 2094 . 2 |- Z (_ W
16 ghomgrpilem1.11 . 2 |- S = (H |` (Z X. Z))
175eleq2i 1541 . . . . . . 7 |- (x e. Z <-> x e. ran F)
18 ffn 3633 . . . . . . . . 9 |- (F:X-->W -> F Fn X)
1912, 18ax-mp 7 . . . . . . . 8 |- F Fn X
20 fvelrnb 3766 . . . . . . . 8 |- (F Fn X -> (x e. ran F <-> E.z e. X (F` z) = x))
2119, 20ax-mp 7 . . . . . . 7 |- (x e. ran F <-> E.z e. X (F` z) = x)
2217, 21bitr 173 . . . . . 6 |- (x e. Z <-> E.z e. X (F` z) = x)
2322biimp 151 . . . . 5 |- (x e. Z -> E.z e. X (F` z) = x)
245eleq2i 1541 . . . . . . 7 |- (y e. Z <-> y e. ran F)
25 fvelrnb 3766 . . . . . . . 8 |- (F Fn X -> (y e. ran F <-> E.w e. X (F` w) = y))
2619, 25ax-mp 7 . . . . . . 7 |- (y e. ran F <-> E.w e. X (F` w) = y)
2724, 26bitr 173 . . . . . 6 |- (y e. Z <-> E.w e. X (F` w) = y)
2827biimp 151 . . . . 5 |- (y e. Z -> E.w e. X (F` w) = y)
2923, 28anim12i 333 . . . 4 |- ((x e. Z /\ y e. Z) -> (E.z e. X (F` z) = x /\ E.w e. X (F` w) = y))
30 reeanv 1781 . . . 4 |- (E.z e. X E.w e. X ((F` z) = x /\ (F` w) = y) <-> (E.z e. X (F` z) = x /\ E.w e. X (F` w) = y))
3129, 30sylibr 200 . . 3 |- ((x e. Z /\ y e. Z) -> E.z e. X E.w e. X ((F` z) = x /\ (F` w) = y))
32 opreq12 3976 . . . . . 6 |- (((F` z) = x /\ (F` w) = y) -> ((F` z)H(F` w)) = (xHy))
3332eleq1d 1543 . . . . 5 |- (((F` z) = x /\ (F` w) = y) -> (((F` z)H(F` w)) e. Z <-> (xHy) e. Z))
34 ghomgrpilem1.5 . . . . . . 7 |- U = (Id` G)
35 ghomgrpilem1.6 . . . . . . 7 |- N = (inv` G)
367, 1, 6, 8, 34, 35, 2, 3, 4, 5, 16ghomgrpilem1 10380 . . . . . 6 |- ((z e. X /\ w e. X) -> ((F` z)H(F` w)) = (F` (zGw)))
378grpcl 8041 . . . . . . . 8 |- ((G e. Grp /\ z e. X /\ w e. X) -> (zGw) e. X)
387, 37mp3an1 905 . . . . . . 7 |- ((z e. X /\ w e. X) -> (zGw) e. X)
39 fnfrn 3640 . . . . . . . . . 10 |- (F Fn X <-> F:X-->ran F)
4019, 39mpbi 189 . . . . . . . . 9 |- F:X-->ran F
41 feq3 3628 . . . . . . . . . 10 |- (Z = ran F -> (F:X-->Z <-> F:X-->ran F))
425, 41ax-mp 7 . . . . . . . . 9 |- (F:X-->Z <-> F:X-->ran F)
4340, 42mpbir 190 . . . . . . . 8 |- F:X-->Z
4443ffvelrni 3821 . . . . . . 7 |- ((zGw) e. X -> (F` (zGw)) e. Z)
4538, 44syl 10 . . . . . 6 |- ((z e. X /\ w e. X) -> (F` (zGw)) e. Z)
4636, 45eqeltrd 1551 . . . . 5 |- ((z e. X /\ w e. X) -> ((F` z)H(F` w)) e. Z)
4733, 46syl5cbi 209 . . . 4 |- ((z e. X /\ w e. X) -> (((F` z) = x /\ (F` w) = y) -> (xHy) e. Z))
4847r19.23aivv 1751 . . 3 |- (E.z e. X E.w e. X ((F` z) = x /\ (F` w) = y) -> (xHy) e. Z)
4931, 48syl 10 . 2 |- ((x e. Z /\ y e. Z) -> (xHy) e. Z)
508, 34grpidcl 8055 . . . . . . . 8 |- (G e. Grp -> U e. X)
517, 50ax-mp 7 . . . . . . 7 |- U e. X
527, 1, 6, 8, 34, 35, 2, 3, 4, 5, 16ghomgrpilem1 10380 . . . . . . 7 |- ((U e. X /\ U e. X) -> ((F` U)H(F` U)) = (F` (UGU)))
5351, 51, 52mp2an 699 . . . . . 6 |- ((F` U)H(F` U)) = (F` (UGU))
548, 34grplid 8057 . . . . . . . 8 |- ((G e. Grp /\ U e. X) -> (UGU) = U)
557, 51, 54mp2an 699 . . . . . . 7 |- (UGU) = U
5655fveq2i 3733 . . . . . 6 |- (F` (UGU)) = (F` U)
5753, 56eqtr 1498 . . . . 5 |- ((F` U)H(F` U)) = (F` U)
58 ffvelrn 3820 . . . . . . 7 |- ((F:X-->W /\ U e. X) -> (F` U) e. W)
5912, 51, 58mp2an 699 . . . . . 6 |- (F` U) e. W
60 eqid 1478 . . . . . . 7 |- (Id` H) = (Id` H)
612, 60grpid 8061 . . . . . 6 |- ((H e. Grp /\ (F` U) e. W) -> ((F` U) = (Id`
H) <-> ((F` U)H(F` U)) = (F` U)))
621, 59, 61mp2an 699 . . . . 5 |- ((F` U) = (Id` H) <-> ((F` U)H(F` U)) = (F` U))
6357, 62mpbir 190 . . . 4 |- (F` U) = (Id` H)
643, 63eqtr4 1501 . . 3 |- T = (F` U)
65 ffvelrn 3820 . . . 4 |- ((F:X-->Z /\ U e. X) -> (F` U) e. Z)
6643, 51, 65mp2an 699 . . 3 |- (F` U) e. Z
6764, 66eqeltr 1547 . 2 |- T e. Z
68 fveq2 3730 . . . . . 6 |- ((F` z) = x -> (M` (F` z)) = (M` x))
6968eleq1d 1543 . . . . 5 |- ((F` z) = x -> ((M` (F` z)) e. Z <-> (M` x) e. Z))
708, 35grpinvcl 8064 . . . . . . . . . . 11 |- ((G e. Grp /\ z e. X) -> (N` z) e. X)
717, 70mpan 697 . . . . . . . . . 10 |- (z e. X -> (N` z) e. X)
727, 1, 6, 8, 34, 35, 2, 3, 4, 5, 16ghomgrpilem1 10380 . . . . . . . . . 10 |- ((z e. X /\ (N` z) e. X) -> ((F` z)H(F` (N` z))) = (F` (zG(N` z))))
7371, 72mpdan 706 . . . . . . . . 9 |- (z e. X -> ((F` z)H(F` (N` z))) = (F` (zG(N` z))))
748, 34, 35grprinv 8067 . . . . . . . . . . 11 |- ((G e. Grp /\ z e. X) -> (zG(N` z)) = U)
757, 74mpan 697 . . . . . . . . . 10 |- (z e. X -> (zG(N` z)) = U)
7675fveq2d 3734 . . . . . . . . 9 |- (z e. X -> (F` (zG(N` z))) = (F` U))
7773, 76eqtrd 1510 . . . . . . . 8 |- (z e. X -> ((F` z)H(F` (N` z))) = (F` U))
7877, 64syl6eqr 1528 . . . . . . 7 |- (z e. X -> ((F` z)H(F` (N` z))) = T)
792, 3, 4grpinvid1 8068 . . . . . . . . 9 |- ((H e. Grp /\ (F` z) e. W /\ (F` (N` z)) e. W) -> ((M` (F` z)) = (F` (N` z)) <-> ((F` z)H(F` (N` z))) = T))
801, 79mp3an1 905 . . . . . . . 8 |- (((F` z) e. W /\ (F` (N` z)) e. W) -> ((M` (F` z)) = (F` (N` z)) <-> ((F` z)H(F` (N` z))) = T))
8112ffvelrni 3821 . . . . . . . 8 |- (z e. X -> (F` z) e. W)
8212ffvelrni 3821 . . . . . . . . 9 |- ((N` z) e. X -> (F` (N` z)) e. W)
8371, 82syl 10 . . . . . . . 8 |- (z e. X -> (F` (N` z)) e. W)
8480, 81, 83sylanc 473 . . . . . . 7 |- (z e. X -> ((M` (F` z)) = (F` (N` z)) <-> ((F` z)H(F` (N` z))) = T))
8578, 84mpbird 196 . . . . . 6 |- (z e. X -> (M` (F` z)) = (F`