Theorem eqfunresadj 33423

Description: Law for adjoining an element to restrictions of functions. (Contributed by Scott Fenton, 6-Dec-2021.)

Assertion

Ref	Expression
eqfunresadj	⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → (𝐹 ↾ (𝑋 ∪ {𝑌})) = (𝐺 ↾ (𝑋 ∪ {𝑌})))

Proof of Theorem eqfunresadj

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

Step	Hyp	Ref	Expression
1		relres 5869	. 2 ⊢ Rel (𝐹 ↾ (𝑋 ∪ {𝑌}))
2		relres 5869	. 2 ⊢ Rel (𝐺 ↾ (𝑋 ∪ {𝑌}))
3		breq 5045	. . . . 5 ⊢ ((𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) → (𝑥(𝐹 ↾ 𝑋)𝑦 ↔ 𝑥(𝐺 ↾ 𝑋)𝑦))
4	3	3ad2ant2 1136	. . . 4 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → (𝑥(𝐹 ↾ 𝑋)𝑦 ↔ 𝑥(𝐺 ↾ 𝑋)𝑦))
5		velsn 4547	. . . . . . 7 ⊢ (𝑥 ∈ {𝑌} ↔ 𝑥 = 𝑌)
6		simp33 1213	. . . . . . . . . 10 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → (𝐹‘𝑌) = (𝐺‘𝑌))
7	6	eqeq1d 2736	. . . . . . . . 9 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → ((𝐹‘𝑌) = 𝑦 ↔ (𝐺‘𝑌) = 𝑦))
8		simp1l 1199	. . . . . . . . . 10 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → Fun 𝐹)
9		simp31 1211	. . . . . . . . . 10 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → 𝑌 ∈ dom 𝐹)
10		funbrfvb 6756	. . . . . . . . . 10 ⊢ ((Fun 𝐹 ∧ 𝑌 ∈ dom 𝐹) → ((𝐹‘𝑌) = 𝑦 ↔ 𝑌𝐹𝑦))
11	8, 9, 10	syl2anc 587	. . . . . . . . 9 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → ((𝐹‘𝑌) = 𝑦 ↔ 𝑌𝐹𝑦))
12		simp1r 1200	. . . . . . . . . 10 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → Fun 𝐺)
13		simp32 1212	. . . . . . . . . 10 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → 𝑌 ∈ dom 𝐺)
14		funbrfvb 6756	. . . . . . . . . 10 ⊢ ((Fun 𝐺 ∧ 𝑌 ∈ dom 𝐺) → ((𝐺‘𝑌) = 𝑦 ↔ 𝑌𝐺𝑦))
15	12, 13, 14	syl2anc 587	. . . . . . . . 9 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → ((𝐺‘𝑌) = 𝑦 ↔ 𝑌𝐺𝑦))
16	7, 11, 15	3bitr3d 312	. . . . . . . 8 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → (𝑌𝐹𝑦 ↔ 𝑌𝐺𝑦))
17		breq1 5046	. . . . . . . . 9 ⊢ (𝑥 = 𝑌 → (𝑥𝐹𝑦 ↔ 𝑌𝐹𝑦))
18		breq1 5046	. . . . . . . . 9 ⊢ (𝑥 = 𝑌 → (𝑥𝐺𝑦 ↔ 𝑌𝐺𝑦))
19	17, 18	bibi12d 349	. . . . . . . 8 ⊢ (𝑥 = 𝑌 → ((𝑥𝐹𝑦 ↔ 𝑥𝐺𝑦) ↔ (𝑌𝐹𝑦 ↔ 𝑌𝐺𝑦)))
20	16, 19	syl5ibrcom 250	. . . . . . 7 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → (𝑥 = 𝑌 → (𝑥𝐹𝑦 ↔ 𝑥𝐺𝑦)))
21	5, 20	syl5bi 245	. . . . . 6 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → (𝑥 ∈ {𝑌} → (𝑥𝐹𝑦 ↔ 𝑥𝐺𝑦)))
22	21	pm5.32d 580	. . . . 5 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → ((𝑥 ∈ {𝑌} ∧ 𝑥𝐹𝑦) ↔ (𝑥 ∈ {𝑌} ∧ 𝑥𝐺𝑦)))
23		vex 3405	. . . . . 6 ⊢ 𝑦 ∈ V
24	23	brresi 5849	. . . . 5 ⊢ (𝑥(𝐹 ↾ {𝑌})𝑦 ↔ (𝑥 ∈ {𝑌} ∧ 𝑥𝐹𝑦))
25	23	brresi 5849	. . . . 5 ⊢ (𝑥(𝐺 ↾ {𝑌})𝑦 ↔ (𝑥 ∈ {𝑌} ∧ 𝑥𝐺𝑦))
26	22, 24, 25	3bitr4g 317	. . . 4 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → (𝑥(𝐹 ↾ {𝑌})𝑦 ↔ 𝑥(𝐺 ↾ {𝑌})𝑦))
27	4, 26	orbi12d 919	. . 3 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → ((𝑥(𝐹 ↾ 𝑋)𝑦 ∨ 𝑥(𝐹 ↾ {𝑌})𝑦) ↔ (𝑥(𝐺 ↾ 𝑋)𝑦 ∨ 𝑥(𝐺 ↾ {𝑌})𝑦)))
28		resundi 5854	. . . . 5 ⊢ (𝐹 ↾ (𝑋 ∪ {𝑌})) = ((𝐹 ↾ 𝑋) ∪ (𝐹 ↾ {𝑌}))
29	28	breqi 5049	. . . 4 ⊢ (𝑥(𝐹 ↾ (𝑋 ∪ {𝑌}))𝑦 ↔ 𝑥((𝐹 ↾ 𝑋) ∪ (𝐹 ↾ {𝑌}))𝑦)
30		brun 5094	. . . 4 ⊢ (𝑥((𝐹 ↾ 𝑋) ∪ (𝐹 ↾ {𝑌}))𝑦 ↔ (𝑥(𝐹 ↾ 𝑋)𝑦 ∨ 𝑥(𝐹 ↾ {𝑌})𝑦))
31	29, 30	bitri 278	. . 3 ⊢ (𝑥(𝐹 ↾ (𝑋 ∪ {𝑌}))𝑦 ↔ (𝑥(𝐹 ↾ 𝑋)𝑦 ∨ 𝑥(𝐹 ↾ {𝑌})𝑦))
32		resundi 5854	. . . . 5 ⊢ (𝐺 ↾ (𝑋 ∪ {𝑌})) = ((𝐺 ↾ 𝑋) ∪ (𝐺 ↾ {𝑌}))
33	32	breqi 5049	. . . 4 ⊢ (𝑥(𝐺 ↾ (𝑋 ∪ {𝑌}))𝑦 ↔ 𝑥((𝐺 ↾ 𝑋) ∪ (𝐺 ↾ {𝑌}))𝑦)
34		brun 5094	. . . 4 ⊢ (𝑥((𝐺 ↾ 𝑋) ∪ (𝐺 ↾ {𝑌}))𝑦 ↔ (𝑥(𝐺 ↾ 𝑋)𝑦 ∨ 𝑥(𝐺 ↾ {𝑌})𝑦))
35	33, 34	bitri 278	. . 3 ⊢ (𝑥(𝐺 ↾ (𝑋 ∪ {𝑌}))𝑦 ↔ (𝑥(𝐺 ↾ 𝑋)𝑦 ∨ 𝑥(𝐺 ↾ {𝑌})𝑦))
36	27, 31, 35	3bitr4g 317	. 2 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → (𝑥(𝐹 ↾ (𝑋 ∪ {𝑌}))𝑦 ↔ 𝑥(𝐺 ↾ (𝑋 ∪ {𝑌}))𝑦))
37	1, 2, 36	eqbrrdiv 5653	1 ⊢ (((Fun 𝐹 ∧ Fun 𝐺) ∧ (𝐹 ↾ 𝑋) = (𝐺 ↾ 𝑋) ∧ (𝑌 ∈ dom 𝐹 ∧ 𝑌 ∈ dom 𝐺 ∧ (𝐹‘𝑌) = (𝐺‘𝑌))) → (𝐹 ↾ (𝑋 ∪ {𝑌})) = (𝐺 ↾ (𝑋 ∪ {𝑌})))

Syntax hints:   → wi 4   ↔ wb 209   ∧ wa 399   ∨ wo 847   ∧ w3a 1089   = wceq 1543   ∈ wcel 2110   ∪ cun 3855  {csn 4531   class class class wbr 5043  dom cdm 5540   ↾ cres 5542  Fun wfun 6363  ‘cfv 6369

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1803  ax-4 1817  ax-5 1918  ax-6 1976  ax-7 2016  ax-8 2112  ax-9 2120  ax-10 2141  ax-11 2158  ax-12 2175  ax-ext 2706  ax-sep 5181  ax-nul 5188  ax-pr 5311

This theorem depends on definitions:  df-bi 210  df-an 400  df-or 848  df-3an 1091  df-tru 1546  df-fal 1556  df-ex 1788  df-nf 1792  df-sb 2071  df-mo 2537  df-eu 2566  df-clab 2713  df-cleq 2726  df-clel 2812  df-nfc 2882  df-ral 3059  df-rex 3060  df-rab 3063  df-v 3403  df-sbc 3688  df-dif 3860  df-un 3862  df-in 3864  df-ss 3874  df-nul 4228  df-if 4430  df-sn 4532  df-pr 4534  df-op 4538  df-uni 4810  df-br 5044  df-opab 5106  df-id 5444  df-xp 5546  df-rel 5547  df-cnv 5548  df-co 5549  df-dm 5550  df-res 5552  df-iota 6327  df-fun 6371  df-fn 6372  df-fv 6377

This theorem is referenced by:  eqfunressuc  33424