Theorem gicer 18892

Description: Isomorphism is an equivalence relation on groups. (Contributed by Mario Carneiro, 21-Apr-2016.) (Proof shortened by AV, 1-May-2021.)

Assertion

Ref	Expression
gicer	⊢ ≃𝑔 Er Grp

Proof of Theorem gicer

Dummy variables 𝑥 𝑦 𝑧 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		df-gic 18876	. . . 4 ⊢ ≃𝑔 = (◡ GrpIso “ (V ∖ 1o))
2		cnvimass 5989	. . . . 5 ⊢ (◡ GrpIso “ (V ∖ 1o)) ⊆ dom GrpIso
3		gimfn 18877	. . . . . 6 ⊢ GrpIso Fn (Grp × Grp)
4	3	fndmi 6537	. . . . 5 ⊢ dom GrpIso = (Grp × Grp)
5	2, 4	sseqtri 3957	. . . 4 ⊢ (◡ GrpIso “ (V ∖ 1o)) ⊆ (Grp × Grp)
6	1, 5	eqsstri 3955	. . 3 ⊢ ≃𝑔 ⊆ (Grp × Grp)
7		relxp 5607	. . 3 ⊢ Rel (Grp × Grp)
8		relss 5692	. . 3 ⊢ ( ≃𝑔 ⊆ (Grp × Grp) → (Rel (Grp × Grp) → Rel ≃𝑔 ))
9	6, 7, 8	mp2 9	. 2 ⊢ Rel ≃𝑔
10		gicsym 18890	. 2 ⊢ (𝑥 ≃𝑔 𝑦 → 𝑦 ≃𝑔 𝑥)
11		gictr 18891	. 2 ⊢ ((𝑥 ≃𝑔 𝑦 ∧ 𝑦 ≃𝑔 𝑧) → 𝑥 ≃𝑔 𝑧)
12		gicref 18887	. . 3 ⊢ (𝑥 ∈ Grp → 𝑥 ≃𝑔 𝑥)
13		giclcl 18888	. . 3 ⊢ (𝑥 ≃𝑔 𝑥 → 𝑥 ∈ Grp)
14	12, 13	impbii 208	. 2 ⊢ (𝑥 ∈ Grp ↔ 𝑥 ≃𝑔 𝑥)
15	9, 10, 11, 14	iseri 8525	1 ⊢ ≃𝑔 Er Grp

Syntax hints:   ∈ wcel 2106  Vcvv 3432   ∖ cdif 3884   ⊆ wss 3887   class class class wbr 5074   × cxp 5587  ^◡ccnv 5588  dom cdm 5589   “ cima 5592  Rel wrel 5594  1_oc1o 8290   Er wer 8495  Grpcgrp 18577   GrpIso cgim 18873   ≃_𝑔 cgic 18874

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1798  ax-4 1812  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-10 2137  ax-11 2154  ax-12 2171  ax-ext 2709  ax-rep 5209  ax-sep 5223  ax-nul 5230  ax-pow 5288  ax-pr 5352  ax-un 7588

This theorem depends on definitions:  df-bi 206  df-an 397  df-or 845  df-3an 1088  df-tru 1542  df-fal 1552  df-ex 1783  df-nf 1787  df-sb 2068  df-mo 2540  df-eu 2569  df-clab 2716  df-cleq 2730  df-clel 2816  df-nfc 2889  df-ne 2944  df-ral 3069  df-rex 3070  df-rmo 3071  df-reu 3072  df-rab 3073  df-v 3434  df-sbc 3717  df-csb 3833  df-dif 3890  df-un 3892  df-in 3894  df-ss 3904  df-nul 4257  df-if 4460  df-pw 4535  df-sn 4562  df-pr 4564  df-op 4568  df-uni 4840  df-iun 4926  df-br 5075  df-opab 5137  df-mpt 5158  df-id 5489  df-xp 5595  df-rel 5596  df-cnv 5597  df-co 5598  df-dm 5599  df-rn 5600  df-res 5601  df-ima 5602  df-suc 6272  df-iota 6391  df-fun 6435  df-fn 6436  df-f 6437  df-f1 6438  df-fo 6439  df-f1o 6440  df-fv 6441  df-riota 7232  df-ov 7278  df-oprab 7279  df-mpo 7280  df-1st 7831  df-2nd 7832  df-1o 8297  df-er 8498  df-map 8617  df-0g 17152  df-mgm 18326  df-sgrp 18375  df-mnd 18386  df-mhm 18430  df-grp 18580  df-ghm 18832  df-gim 18875  df-gic 18876

This theorem is referenced by: (None)