Theorem isoini 7209

Description: Isomorphisms preserve initial segments. Proposition 6.31(2) of [TakeutiZaring] p. 33. (Contributed by NM, 20-Apr-2004.)

Assertion

Ref	Expression
isoini	⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ 𝐷 ∈ 𝐴) → (𝐻 “ (𝐴 ∩ (◡𝑅 “ {𝐷}))) = (𝐵 ∩ (◡𝑆 “ {(𝐻‘𝐷)})))

Proof of Theorem isoini

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

Step	Hyp	Ref	Expression
1		dfima2 5971	. 2 ⊢ (𝐻 “ (𝐴 ∩ (◡𝑅 “ {𝐷}))) = {𝑦 ∣ ∃𝑥 ∈ (𝐴 ∩ (◡𝑅 “ {𝐷}))𝑥𝐻𝑦}
2		elin 3903	. . . 4 ⊢ (𝑦 ∈ (𝐵 ∩ (◡𝑆 “ {(𝐻‘𝐷)})) ↔ (𝑦 ∈ 𝐵 ∧ 𝑦 ∈ (◡𝑆 “ {(𝐻‘𝐷)})))
3		isof1o 7194	. . . . . . . . 9 ⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → 𝐻:𝐴–1-1-onto→𝐵)
4		f1ofo 6723	. . . . . . . . 9 ⊢ (𝐻:𝐴–1-1-onto→𝐵 → 𝐻:𝐴–onto→𝐵)
5		forn 6691	. . . . . . . . . 10 ⊢ (𝐻:𝐴–onto→𝐵 → ran 𝐻 = 𝐵)
6	5	eleq2d 2824	. . . . . . . . 9 ⊢ (𝐻:𝐴–onto→𝐵 → (𝑦 ∈ ran 𝐻 ↔ 𝑦 ∈ 𝐵))
7	3, 4, 6	3syl 18	. . . . . . . 8 ⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → (𝑦 ∈ ran 𝐻 ↔ 𝑦 ∈ 𝐵))
8		f1ofn 6717	. . . . . . . . 9 ⊢ (𝐻:𝐴–1-1-onto→𝐵 → 𝐻 Fn 𝐴)
9		fvelrnb 6830	. . . . . . . . 9 ⊢ (𝐻 Fn 𝐴 → (𝑦 ∈ ran 𝐻 ↔ ∃𝑥 ∈ 𝐴 (𝐻‘𝑥) = 𝑦))
10	3, 8, 9	3syl 18	. . . . . . . 8 ⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → (𝑦 ∈ ran 𝐻 ↔ ∃𝑥 ∈ 𝐴 (𝐻‘𝑥) = 𝑦))
11	7, 10	bitr3d 280	. . . . . . 7 ⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → (𝑦 ∈ 𝐵 ↔ ∃𝑥 ∈ 𝐴 (𝐻‘𝑥) = 𝑦))
12		fvex 6787	. . . . . . . 8 ⊢ (𝐻‘𝐷) ∈ V
13		vex 3436	. . . . . . . . 9 ⊢ 𝑦 ∈ V
14	13	eliniseg 6002	. . . . . . . 8 ⊢ ((𝐻‘𝐷) ∈ V → (𝑦 ∈ (◡𝑆 “ {(𝐻‘𝐷)}) ↔ 𝑦𝑆(𝐻‘𝐷)))
15	12, 14	mp1i 13	. . . . . . 7 ⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → (𝑦 ∈ (◡𝑆 “ {(𝐻‘𝐷)}) ↔ 𝑦𝑆(𝐻‘𝐷)))
16	11, 15	anbi12d 631	. . . . . 6 ⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → ((𝑦 ∈ 𝐵 ∧ 𝑦 ∈ (◡𝑆 “ {(𝐻‘𝐷)})) ↔ (∃𝑥 ∈ 𝐴 (𝐻‘𝑥) = 𝑦 ∧ 𝑦𝑆(𝐻‘𝐷))))
17	16	adantr 481	. . . . 5 ⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ 𝐷 ∈ 𝐴) → ((𝑦 ∈ 𝐵 ∧ 𝑦 ∈ (◡𝑆 “ {(𝐻‘𝐷)})) ↔ (∃𝑥 ∈ 𝐴 (𝐻‘𝑥) = 𝑦 ∧ 𝑦𝑆(𝐻‘𝐷))))
18		elin 3903	. . . . . . . . . . . 12 ⊢ (𝑥 ∈ (𝐴 ∩ (◡𝑅 “ {𝐷})) ↔ (𝑥 ∈ 𝐴 ∧ 𝑥 ∈ (◡𝑅 “ {𝐷})))
19		vex 3436	. . . . . . . . . . . . . 14 ⊢ 𝑥 ∈ V
20	19	eliniseg 6002	. . . . . . . . . . . . 13 ⊢ (𝐷 ∈ 𝐴 → (𝑥 ∈ (◡𝑅 “ {𝐷}) ↔ 𝑥𝑅𝐷))
21	20	anbi2d 629	. . . . . . . . . . . 12 ⊢ (𝐷 ∈ 𝐴 → ((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ (◡𝑅 “ {𝐷})) ↔ (𝑥 ∈ 𝐴 ∧ 𝑥𝑅𝐷)))
22	18, 21	bitrid 282	. . . . . . . . . . 11 ⊢ (𝐷 ∈ 𝐴 → (𝑥 ∈ (𝐴 ∩ (◡𝑅 “ {𝐷})) ↔ (𝑥 ∈ 𝐴 ∧ 𝑥𝑅𝐷)))
23	22	anbi1d 630	. . . . . . . . . 10 ⊢ (𝐷 ∈ 𝐴 → ((𝑥 ∈ (𝐴 ∩ (◡𝑅 “ {𝐷})) ∧ 𝑥𝐻𝑦) ↔ ((𝑥 ∈ 𝐴 ∧ 𝑥𝑅𝐷) ∧ 𝑥𝐻𝑦)))
24		anass 469	. . . . . . . . . 10 ⊢ (((𝑥 ∈ 𝐴 ∧ 𝑥𝑅𝐷) ∧ 𝑥𝐻𝑦) ↔ (𝑥 ∈ 𝐴 ∧ (𝑥𝑅𝐷 ∧ 𝑥𝐻𝑦)))
25	23, 24	bitrdi 287	. . . . . . . . 9 ⊢ (𝐷 ∈ 𝐴 → ((𝑥 ∈ (𝐴 ∩ (◡𝑅 “ {𝐷})) ∧ 𝑥𝐻𝑦) ↔ (𝑥 ∈ 𝐴 ∧ (𝑥𝑅𝐷 ∧ 𝑥𝐻𝑦))))
26	25	adantl 482	. . . . . . . 8 ⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ 𝐷 ∈ 𝐴) → ((𝑥 ∈ (𝐴 ∩ (◡𝑅 “ {𝐷})) ∧ 𝑥𝐻𝑦) ↔ (𝑥 ∈ 𝐴 ∧ (𝑥𝑅𝐷 ∧ 𝑥𝐻𝑦))))
27		isorel 7197	. . . . . . . . . . . . . 14 ⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑥 ∈ 𝐴 ∧ 𝐷 ∈ 𝐴)) → (𝑥𝑅𝐷 ↔ (𝐻‘𝑥)𝑆(𝐻‘𝐷)))
28	3, 8	syl 17	. . . . . . . . . . . . . . . 16 ⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → 𝐻 Fn 𝐴)
29		fnbrfvb 6822	. . . . . . . . . . . . . . . . 17 ⊢ ((𝐻 Fn 𝐴 ∧ 𝑥 ∈ 𝐴) → ((𝐻‘𝑥) = 𝑦 ↔ 𝑥𝐻𝑦))
30	29	bicomd 222	. . . . . . . . . . . . . . . 16 ⊢ ((𝐻 Fn 𝐴 ∧ 𝑥 ∈ 𝐴) → (𝑥𝐻𝑦 ↔ (𝐻‘𝑥) = 𝑦))
31	28, 30	sylan 580	. . . . . . . . . . . . . . 15 ⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ 𝑥 ∈ 𝐴) → (𝑥𝐻𝑦 ↔ (𝐻‘𝑥) = 𝑦))
32	31	adantrr 714	. . . . . . . . . . . . . 14 ⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑥 ∈ 𝐴 ∧ 𝐷 ∈ 𝐴)) → (𝑥𝐻𝑦 ↔ (𝐻‘𝑥) = 𝑦))
33	27, 32	anbi12d 631	. . . . . . . . . . . . 13 ⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑥 ∈ 𝐴 ∧ 𝐷 ∈ 𝐴)) → ((𝑥𝑅𝐷 ∧ 𝑥𝐻𝑦) ↔ ((𝐻‘𝑥)𝑆(𝐻‘𝐷) ∧ (𝐻‘𝑥) = 𝑦)))
34		ancom 461	. . . . . . . . . . . . . 14 ⊢ (((𝐻‘𝑥)𝑆(𝐻‘𝐷) ∧ (𝐻‘𝑥) = 𝑦) ↔ ((𝐻‘𝑥) = 𝑦 ∧ (𝐻‘𝑥)𝑆(𝐻‘𝐷)))
35		breq1 5077	. . . . . . . . . . . . . . 15 ⊢ ((𝐻‘𝑥) = 𝑦 → ((𝐻‘𝑥)𝑆(𝐻‘𝐷) ↔ 𝑦𝑆(𝐻‘𝐷)))
36	35	pm5.32i 575	. . . . . . . . . . . . . 14 ⊢ (((𝐻‘𝑥) = 𝑦 ∧ (𝐻‘𝑥)𝑆(𝐻‘𝐷)) ↔ ((𝐻‘𝑥) = 𝑦 ∧ 𝑦𝑆(𝐻‘𝐷)))
37	34, 36	bitri 274	. . . . . . . . . . . . 13 ⊢ (((𝐻‘𝑥)𝑆(𝐻‘𝐷) ∧ (𝐻‘𝑥) = 𝑦) ↔ ((𝐻‘𝑥) = 𝑦 ∧ 𝑦𝑆(𝐻‘𝐷)))
38	33, 37	bitrdi 287	. . . . . . . . . . . 12 ⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑥 ∈ 𝐴 ∧ 𝐷 ∈ 𝐴)) → ((𝑥𝑅𝐷 ∧ 𝑥𝐻𝑦) ↔ ((𝐻‘𝑥) = 𝑦 ∧ 𝑦𝑆(𝐻‘𝐷))))
39	38	exp32 421	. . . . . . . . . . 11 ⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → (𝑥 ∈ 𝐴 → (𝐷 ∈ 𝐴 → ((𝑥𝑅𝐷 ∧ 𝑥𝐻𝑦) ↔ ((𝐻‘𝑥) = 𝑦 ∧ 𝑦𝑆(𝐻‘𝐷))))))
40	39	com23 86	. . . . . . . . . 10 ⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → (𝐷 ∈ 𝐴 → (𝑥 ∈ 𝐴 → ((𝑥𝑅𝐷 ∧ 𝑥𝐻𝑦) ↔ ((𝐻‘𝑥) = 𝑦 ∧ 𝑦𝑆(𝐻‘𝐷))))))
41	40	imp 407	. . . . . . . . 9 ⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ 𝐷 ∈ 𝐴) → (𝑥 ∈ 𝐴 → ((𝑥𝑅𝐷 ∧ 𝑥𝐻𝑦) ↔ ((𝐻‘𝑥) = 𝑦 ∧ 𝑦𝑆(𝐻‘𝐷)))))
42	41	pm5.32d 577	. . . . . . . 8 ⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ 𝐷 ∈ 𝐴) → ((𝑥 ∈ 𝐴 ∧ (𝑥𝑅𝐷 ∧ 𝑥𝐻𝑦)) ↔ (𝑥 ∈ 𝐴 ∧ ((𝐻‘𝑥) = 𝑦 ∧ 𝑦𝑆(𝐻‘𝐷)))))
43	26, 42	bitrd 278	. . . . . . 7 ⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ 𝐷 ∈ 𝐴) → ((𝑥 ∈ (𝐴 ∩ (◡𝑅 “ {𝐷})) ∧ 𝑥𝐻𝑦) ↔ (𝑥 ∈ 𝐴 ∧ ((𝐻‘𝑥) = 𝑦 ∧ 𝑦𝑆(𝐻‘𝐷)))))
44	43	rexbidv2 3224	. . . . . 6 ⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ 𝐷 ∈ 𝐴) → (∃𝑥 ∈ (𝐴 ∩ (◡𝑅 “ {𝐷}))𝑥𝐻𝑦 ↔ ∃𝑥 ∈ 𝐴 ((𝐻‘𝑥) = 𝑦 ∧ 𝑦𝑆(𝐻‘𝐷))))
45		r19.41v 3276	. . . . . 6 ⊢ (∃𝑥 ∈ 𝐴 ((𝐻‘𝑥) = 𝑦 ∧ 𝑦𝑆(𝐻‘𝐷)) ↔ (∃𝑥 ∈ 𝐴 (𝐻‘𝑥) = 𝑦 ∧ 𝑦𝑆(𝐻‘𝐷)))
46	44, 45	bitrdi 287	. . . . 5 ⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ 𝐷 ∈ 𝐴) → (∃𝑥 ∈ (𝐴 ∩ (◡𝑅 “ {𝐷}))𝑥𝐻𝑦 ↔ (∃𝑥 ∈ 𝐴 (𝐻‘𝑥) = 𝑦 ∧ 𝑦𝑆(𝐻‘𝐷))))
47	17, 46	bitr4d 281	. . . 4 ⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ 𝐷 ∈ 𝐴) → ((𝑦 ∈ 𝐵 ∧ 𝑦 ∈ (◡𝑆 “ {(𝐻‘𝐷)})) ↔ ∃𝑥 ∈ (𝐴 ∩ (◡𝑅 “ {𝐷}))𝑥𝐻𝑦))
48	2, 47	bitrid 282	. . 3 ⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ 𝐷 ∈ 𝐴) → (𝑦 ∈ (𝐵 ∩ (◡𝑆 “ {(𝐻‘𝐷)})) ↔ ∃𝑥 ∈ (𝐴 ∩ (◡𝑅 “ {𝐷}))𝑥𝐻𝑦))
49	48	abbi2dv 2877	. 2 ⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ 𝐷 ∈ 𝐴) → (𝐵 ∩ (◡𝑆 “ {(𝐻‘𝐷)})) = {𝑦 ∣ ∃𝑥 ∈ (𝐴 ∩ (◡𝑅 “ {𝐷}))𝑥𝐻𝑦})
50	1, 49	eqtr4id 2797	1 ⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ 𝐷 ∈ 𝐴) → (𝐻 “ (𝐴 ∩ (◡𝑅 “ {𝐷}))) = (𝐵 ∩ (◡𝑆 “ {(𝐻‘𝐷)})))

Syntax hints:   → wi 4   ↔ wb 205   ∧ wa 396   = wceq 1539   ∈ wcel 2106  {cab 2715  ∃wrex 3065  Vcvv 3432   ∩ cin 3886  {csn 4561   class class class wbr 5074  ^◡ccnv 5588  ran crn 5590   “ cima 5592   Fn wfn 6428  –onto→wfo 6431  –1-1-onto→wf1o 6432  ‘cfv 6433   Isom wiso 6434

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-sep 5223  ax-nul 5230  ax-pr 5352

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-ral 3069  df-rex 3070  df-rab 3073  df-v 3434  df-dif 3890  df-un 3892  df-in 3894  df-ss 3904  df-nul 4257  df-if 4460  df-sn 4562  df-pr 4564  df-op 4568  df-uni 4840  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-iota 6391  df-fun 6435  df-fn 6436  df-f 6437  df-f1 6438  df-fo 6439  df-f1o 6440  df-fv 6441  df-isom 6442

This theorem is referenced by:  isoini2  7210  isoselem  7212  infxpenlem  9769