Theorem qusgrp2 13564

Description: Prove that a quotient structure is a group. (Contributed by Mario Carneiro, 14-Jun-2015.) (Revised by Mario Carneiro, 12-Aug-2015.)

Hypotheses

Ref	Expression
qusgrp2.u	|- ( ph -> U = ( R /.s .~ ) )
qusgrp2.v	|- ( ph -> V = ( Base ` R ) )
qusgrp2.p	|- ( ph -> .+ = ( +g ` R ) )
qusgrp2.r	|- ( ph -> .~ Er V )
qusgrp2.x	|- ( ph -> R e. X )
qusgrp2.e	|- ( ph -> ( ( a .~ p /\ b .~ q ) -> ( a .+ b ) .~ ( p .+ q ) ) )
qusgrp2.1	|- ( ( ph /\ x e. V /\ y e. V ) -> ( x .+ y ) e. V )
qusgrp2.2	|- ( ( ph /\ ( x e. V /\ y e. V /\ z e. V ) ) -> ( ( x .+ y ) .+ z ) .~ ( x .+ ( y .+ z ) ) )
qusgrp2.3	|- ( ph -> .0. e. V )
qusgrp2.4	|- ( ( ph /\ x e. V ) -> ( .0. .+ x ) .~ x )
qusgrp2.5	|- ( ( ph /\ x e. V ) -> N e. V )
qusgrp2.6	|- ( ( ph /\ x e. V ) -> ( N .+ x ) .~ .0. )

Assertion

Ref	Expression
qusgrp2	|- ( ph -> ( U e. Grp /\ [ .0. ] .~ = ( 0g ` U ) ) )

Distinct variable groups:   a, b, p, q, x, y, z, .~   .0. , a, b, p, q, x   N, p   R, p, q   .+ , a, b, p, q, x, y   ph, a, b, p, q, x, y, z   V, a, b, p, q, x, y, z   U, a, b, p, q, x, y, z

Allowed substitution hints:   .+ ( z)   R( x, y, z, a, b)   N( x, y, z, q, a, b)   X( x, y, z, q, p, a, b)   .0. ( y, z)

Proof of Theorem qusgrp2

Dummy variable u is distinct from all other variables.

Step	Hyp	Ref	Expression
1		qusgrp2.u	. . . 4 |- ( ph -> U = ( R /.s .~ ) )
2		qusgrp2.v	. . . 4 |- ( ph -> V = ( Base ` R ) )
3		eqid 2207	. . . 4 |- ( u e. V |-> [ u ] .~ ) = ( u e. V |-> [ u ] .~ )
4		qusgrp2.r	. . . . 5 |- ( ph -> .~ Er V )
5		basfn 13005	. . . . . . 7 |- Base Fn _V
6		qusgrp2.x	. . . . . . . 8 |- ( ph -> R e. X )
7	6	elexd 2790	. . . . . . 7 |- ( ph -> R e. _V )
8		funfvex 5616	. . . . . . . 8 |- ( ( Fun Base /\ R e. dom Base ) -> ( Base ` R ) e. _V )
9	8	funfni 5395	. . . . . . 7 |- ( ( Base Fn _V /\ R e. _V ) -> ( Base ` R ) e. _V )
10	5, 7, 9	sylancr 414	. . . . . 6 |- ( ph -> ( Base ` R ) e. _V )
11	2, 10	eqeltrd 2284	. . . . 5 |- ( ph -> V e. _V )
12		erex 6667	. . . . 5 |- ( .~ Er V -> ( V e. _V -> .~ e. _V ) )
13	4, 11, 12	sylc 62	. . . 4 |- ( ph -> .~ e. _V )
14	1, 2, 3, 13, 6	qusval 13270	. . 3 |- ( ph -> U = ( ( u e. V |-> [ u ] .~ ) "s R ) )
15		qusgrp2.p	. . 3 |- ( ph -> .+ = ( +g ` R ) )
16	1, 2, 3, 13, 6	quslem 13271	. . 3 |- ( ph -> ( u e. V |-> [ u ] .~ ) : V -onto-> ( V /. .~ ) )
17		qusgrp2.1	. . . . 5 |- ( ( ph /\ x e. V /\ y e. V ) -> ( x .+ y ) e. V )
18	17	3expb 1207	. . . 4 |- ( ( ph /\ ( x e. V /\ y e. V ) ) -> ( x .+ y ) e. V )
19		qusgrp2.e	. . . 4 |- ( ph -> ( ( a .~ p /\ b .~ q ) -> ( a .+ b ) .~ ( p .+ q ) ) )
20	4, 11, 3, 18, 19	ercpbl 13278	. . 3 |- ( ( ph /\ ( a e. V /\ b e. V ) /\ ( p e. V /\ q e. V ) ) -> ( ( ( ( u e. V |-> [ u ] .~ ) ` a ) = ( ( u e. V |-> [ u ] .~ ) ` p ) /\ ( ( u e. V |-> [ u ] .~ ) ` b ) = ( ( u e. V |-> [ u ] .~ ) ` q ) ) -> ( ( u e. V |-> [ u ] .~ ) ` ( a .+ b ) ) = ( ( u e. V |-> [ u ] .~ ) ` ( p .+ q ) ) ) )
21	4	adantr 276	. . . . 5 |- ( ( ph /\ ( x e. V /\ y e. V /\ z e. V ) ) -> .~ Er V )
22		qusgrp2.2	. . . . 5 |- ( ( ph /\ ( x e. V /\ y e. V /\ z e. V ) ) -> ( ( x .+ y ) .+ z ) .~ ( x .+ ( y .+ z ) ) )
23	21, 22	erthi 6691	. . . 4 |- ( ( ph /\ ( x e. V /\ y e. V /\ z e. V ) ) -> [ ( ( x .+ y ) .+ z ) ] .~ = [ ( x .+ ( y .+ z ) ) ] .~ )
24	11	adantr 276	. . . . 5 |- ( ( ph /\ ( x e. V /\ y e. V /\ z e. V ) ) -> V e. _V )
25	21, 22	ercl 6654	. . . . 5 |- ( ( ph /\ ( x e. V /\ y e. V /\ z e. V ) ) -> ( ( x .+ y ) .+ z ) e. V )
26	21, 24, 3, 25	divsfvalg 13276	. . . 4 |- ( ( ph /\ ( x e. V /\ y e. V /\ z e. V ) ) -> ( ( u e. V |-> [ u ] .~ ) ` ( ( x .+ y ) .+ z ) ) = [ ( ( x .+ y ) .+ z ) ] .~ )
27	21, 22	ercl2 6656	. . . . 5 |- ( ( ph /\ ( x e. V /\ y e. V /\ z e. V ) ) -> ( x .+ ( y .+ z ) ) e. V )
28	21, 24, 3, 27	divsfvalg 13276	. . . 4 |- ( ( ph /\ ( x e. V /\ y e. V /\ z e. V ) ) -> ( ( u e. V |-> [ u ] .~ ) ` ( x .+ ( y .+ z ) ) ) = [ ( x .+ ( y .+ z ) ) ] .~ )
29	23, 26, 28	3eqtr4d 2250	. . 3 |- ( ( ph /\ ( x e. V /\ y e. V /\ z e. V ) ) -> ( ( u e. V |-> [ u ] .~ ) ` ( ( x .+ y ) .+ z ) ) = ( ( u e. V |-> [ u ] .~ ) ` ( x .+ ( y .+ z ) ) ) )
30		qusgrp2.3	. . 3 |- ( ph -> .0. e. V )
31	4	adantr 276	. . . . 5 |- ( ( ph /\ x e. V ) -> .~ Er V )
32		qusgrp2.4	. . . . 5 |- ( ( ph /\ x e. V ) -> ( .0. .+ x ) .~ x )
33	31, 32	erthi 6691	. . . 4 |- ( ( ph /\ x e. V ) -> [ ( .0. .+ x ) ] .~ = [ x ] .~ )
34	11	adantr 276	. . . . 5 |- ( ( ph /\ x e. V ) -> V e. _V )
35	31, 32	ercl 6654	. . . . 5 |- ( ( ph /\ x e. V ) -> ( .0. .+ x ) e. V )
36	31, 34, 3, 35	divsfvalg 13276	. . . 4 |- ( ( ph /\ x e. V ) -> ( ( u e. V |-> [ u ] .~ ) ` ( .0. .+ x ) ) = [ ( .0. .+ x ) ] .~ )
37		simpr 110	. . . . 5 |- ( ( ph /\ x e. V ) -> x e. V )
38	31, 34, 3, 37	divsfvalg 13276	. . . 4 |- ( ( ph /\ x e. V ) -> ( ( u e. V |-> [ u ] .~ ) ` x ) = [ x ] .~ )
39	33, 36, 38	3eqtr4d 2250	. . 3 |- ( ( ph /\ x e. V ) -> ( ( u e. V |-> [ u ] .~ ) ` ( .0. .+ x ) ) = ( ( u e. V |-> [ u ] .~ ) ` x ) )
40		qusgrp2.5	. . 3 |- ( ( ph /\ x e. V ) -> N e. V )
41		qusgrp2.6	. . . . . 6 |- ( ( ph /\ x e. V ) -> ( N .+ x ) .~ .0. )
42	31, 41	ersym 6655	. . . . 5 |- ( ( ph /\ x e. V ) -> .0. .~ ( N .+ x ) )
43	31, 42	erthi 6691	. . . 4 |- ( ( ph /\ x e. V ) -> [ .0. ] .~ = [ ( N .+ x ) ] .~ )
44	30	adantr 276	. . . . 5 |- ( ( ph /\ x e. V ) -> .0. e. V )
45	31, 34, 3, 44	divsfvalg 13276	. . . 4 |- ( ( ph /\ x e. V ) -> ( ( u e. V |-> [ u ] .~ ) ` .0. ) = [ .0. ] .~ )
46	31, 41	ercl 6654	. . . . 5 |- ( ( ph /\ x e. V ) -> ( N .+ x ) e. V )
47	31, 34, 3, 46	divsfvalg 13276	. . . 4 |- ( ( ph /\ x e. V ) -> ( ( u e. V |-> [ u ] .~ ) ` ( N .+ x ) ) = [ ( N .+ x ) ] .~ )
48	43, 45, 47	3eqtr4rd 2251	. . 3 |- ( ( ph /\ x e. V ) -> ( ( u e. V |-> [ u ] .~ ) ` ( N .+ x ) ) = ( ( u e. V |-> [ u ] .~ ) ` .0. ) )
49	14, 2, 15, 16, 20, 6, 17, 29, 30, 39, 40, 48	imasgrp2 13561	. 2 |- ( ph -> ( U e. Grp /\ ( ( u e. V |-> [ u ] .~ ) ` .0. ) = ( 0g ` U ) ) )
50	4, 11, 3, 30	divsfvalg 13276	. . . . 5 |- ( ph -> ( ( u e. V |-> [ u ] .~ ) ` .0. ) = [ .0. ] .~ )
51	50	eqcomd 2213	. . . 4 |- ( ph -> [ .0. ] .~ = ( ( u e. V |-> [ u ] .~ ) ` .0. ) )
52	51	eqeq1d 2216	. . 3 |- ( ph -> ( [ .0. ] .~ = ( 0g ` U ) <-> ( ( u e. V |-> [ u ] .~ ) ` .0. ) = ( 0g ` U ) ) )
53	52	anbi2d 464	. 2 |- ( ph -> ( ( U e. Grp /\ [ .0. ] .~ = ( 0g ` U ) ) <-> ( U e. Grp /\ ( ( u e. V |-> [ u ] .~ ) ` .0. ) = ( 0g ` U ) ) ) )
54	49, 53	mpbird 167	1 |- ( ph -> ( U e. Grp /\ [ .0. ] .~ = ( 0g ` U ) ) )

Syntax hints:   -> wi 4   /\ wa 104   /\ w3a 981   = wceq 1373   e. wcel 2178   _Vcvv 2776   class class class wbr 4059   |-> cmpt 4121   Fn wfn 5285   ` cfv 5290  (class class class)co 5967   Er wer 6640   [cec 6641   /.cqs 6642   Basecbs 12947   +g cplusg 13024   0gc0g 13203   /._s cqus 13247   Grpcgrp 13447

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-in1 615  ax-in2 616  ax-io 711  ax-5 1471  ax-7 1472  ax-gen 1473  ax-ie1 1517  ax-ie2 1518  ax-8 1528  ax-10 1529  ax-11 1530  ax-i12 1531  ax-bndl 1533  ax-4 1534  ax-17 1550  ax-i9 1554  ax-ial 1558  ax-i5r 1559  ax-13 2180  ax-14 2181  ax-ext 2189  ax-coll 4175  ax-sep 4178  ax-pow 4234  ax-pr 4269  ax-un 4498  ax-setind 4603  ax-cnex 8051  ax-resscn 8052  ax-1cn 8053  ax-1re 8054  ax-icn 8055  ax-addcl 8056  ax-addrcl 8057  ax-mulcl 8058  ax-addcom 8060  ax-addass 8062  ax-i2m1 8065  ax-0lt1 8066  ax-0id 8068  ax-rnegex 8069  ax-pre-ltirr 8072  ax-pre-lttrn 8074  ax-pre-ltadd 8076

This theorem depends on definitions:  df-bi 117  df-3or 982  df-3an 983  df-tru 1376  df-fal 1379  df-nf 1485  df-sb 1787  df-eu 2058  df-mo 2059  df-clab 2194  df-cleq 2200  df-clel 2203  df-nfc 2339  df-ne 2379  df-nel 2474  df-ral 2491  df-rex 2492  df-reu 2493  df-rmo 2494  df-rab 2495  df-v 2778  df-sbc 3006  df-csb 3102  df-dif 3176  df-un 3178  df-in 3180  df-ss 3187  df-nul 3469  df-pw 3628  df-sn 3649  df-pr 3650  df-tp 3651  df-op 3652  df-uni 3865  df-int 3900  df-iun 3943  df-br 4060  df-opab 4122  df-mpt 4123  df-id 4358  df-xp 4699  df-rel 4700  df-cnv 4701  df-co 4702  df-dm 4703  df-rn 4704  df-res 4705  df-ima 4706  df-iota 5251  df-fun 5292  df-fn 5293  df-f 5294  df-f1 5295  df-fo 5296  df-f1o 5297  df-fv 5298  df-riota 5922  df-ov 5970  df-oprab 5971  df-mpo 5972  df-er 6643  df-ec 6645  df-qs 6649  df-pnf 8144  df-mnf 8145  df-ltxr 8147  df-inn 9072  df-2 9130  df-3 9131  df-ndx 12950  df-slot 12951  df-base 12953  df-plusg 13037  df-mulr 13038  df-0g 13205  df-iimas 13249  df-qus 13250  df-mgm 13303  df-sgrp 13349  df-mnd 13364  df-grp 13450

This theorem is referenced by:  qusgrp  13683