Theorem tgjustf 28935

Description: Given any function 𝐹, equality of the image by 𝐹 is an equivalence relation. (Contributed by Thierry Arnoux, 25-Jan-2023.)

Assertion

Ref	Expression
tgjustf	⊢ (𝐴 ∈ 𝑉 → ∃𝑟(𝑟 Er 𝐴 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥𝑟𝑦 ↔ (𝐹‘𝑥) = (𝐹‘𝑦))))

Distinct variable groups:   𝐴,𝑟,𝑥,𝑦   𝐹,𝑟,𝑥,𝑦

Allowed substitution hints:   𝑉(𝑥, 𝑦, 𝑟)

Proof of Theorem tgjustf

Dummy variables 𝑢 𝑣 𝑧 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		relopabv 5798	. . 3 ⊢ Rel {⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}
2		ancom 466	. . . . . 6 ⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) ↔ (𝑦 ∈ 𝐴 ∧ 𝑥 ∈ 𝐴))
3		eqcom 2767	. . . . . 6 ⊢ ((𝐹‘𝑥) = (𝐹‘𝑦) ↔ (𝐹‘𝑦) = (𝐹‘𝑥))
4	2, 3	anbi12i 640	. . . . 5 ⊢ (((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) ∧ (𝐹‘𝑥) = (𝐹‘𝑦)) ↔ ((𝑦 ∈ 𝐴 ∧ 𝑥 ∈ 𝐴) ∧ (𝐹‘𝑦) = (𝐹‘𝑥)))
5		simpl 488	. . . . . . . 8 ⊢ ((𝑢 = 𝑥 ∧ 𝑣 = 𝑦) → 𝑢 = 𝑥)
6	5	fveq2d 6889	. . . . . . 7 ⊢ ((𝑢 = 𝑥 ∧ 𝑣 = 𝑦) → (𝐹‘𝑢) = (𝐹‘𝑥))
7		simpr 490	. . . . . . . 8 ⊢ ((𝑢 = 𝑥 ∧ 𝑣 = 𝑦) → 𝑣 = 𝑦)
8	7	fveq2d 6889	. . . . . . 7 ⊢ ((𝑢 = 𝑥 ∧ 𝑣 = 𝑦) → (𝐹‘𝑣) = (𝐹‘𝑦))
9	6, 8	eqeq12d 2776	. . . . . 6 ⊢ ((𝑢 = 𝑥 ∧ 𝑣 = 𝑦) → ((𝐹‘𝑢) = (𝐹‘𝑣) ↔ (𝐹‘𝑥) = (𝐹‘𝑦)))
10		eqid 2760	. . . . . 6 ⊢ {⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))} = {⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}
11	9, 10	brab2a 5743	. . . . 5 ⊢ (𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑦 ↔ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) ∧ (𝐹‘𝑥) = (𝐹‘𝑦)))
12		simpl 488	. . . . . . . 8 ⊢ ((𝑢 = 𝑦 ∧ 𝑣 = 𝑥) → 𝑢 = 𝑦)
13	12	fveq2d 6889	. . . . . . 7 ⊢ ((𝑢 = 𝑦 ∧ 𝑣 = 𝑥) → (𝐹‘𝑢) = (𝐹‘𝑦))
14		simpr 490	. . . . . . . 8 ⊢ ((𝑢 = 𝑦 ∧ 𝑣 = 𝑥) → 𝑣 = 𝑥)
15	14	fveq2d 6889	. . . . . . 7 ⊢ ((𝑢 = 𝑦 ∧ 𝑣 = 𝑥) → (𝐹‘𝑣) = (𝐹‘𝑥))
16	13, 15	eqeq12d 2776	. . . . . 6 ⊢ ((𝑢 = 𝑦 ∧ 𝑣 = 𝑥) → ((𝐹‘𝑢) = (𝐹‘𝑣) ↔ (𝐹‘𝑦) = (𝐹‘𝑥)))
17	16, 10	brab2a 5743	. . . . 5 ⊢ (𝑦{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑥 ↔ ((𝑦 ∈ 𝐴 ∧ 𝑥 ∈ 𝐴) ∧ (𝐹‘𝑦) = (𝐹‘𝑥)))
18	4, 11, 17	3bitr4i 306	. . . 4 ⊢ (𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑦 ↔ 𝑦{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑥)
19	18	biimpi 219	. . 3 ⊢ (𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑦 → 𝑦{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑥)
20		simplll 787	. . . . 5 ⊢ ((((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) ∧ (𝐹‘𝑥) = (𝐹‘𝑦)) ∧ ((𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴) ∧ (𝐹‘𝑦) = (𝐹‘𝑧))) → 𝑥 ∈ 𝐴)
21		simprlr 792	. . . . 5 ⊢ ((((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) ∧ (𝐹‘𝑥) = (𝐹‘𝑦)) ∧ ((𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴) ∧ (𝐹‘𝑦) = (𝐹‘𝑧))) → 𝑧 ∈ 𝐴)
22		simplr 781	. . . . . 6 ⊢ ((((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) ∧ (𝐹‘𝑥) = (𝐹‘𝑦)) ∧ ((𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴) ∧ (𝐹‘𝑦) = (𝐹‘𝑧))) → (𝐹‘𝑥) = (𝐹‘𝑦))
23		simprr 785	. . . . . 6 ⊢ ((((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) ∧ (𝐹‘𝑥) = (𝐹‘𝑦)) ∧ ((𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴) ∧ (𝐹‘𝑦) = (𝐹‘𝑧))) → (𝐹‘𝑦) = (𝐹‘𝑧))
24	22, 23	eqtrd 2795	. . . . 5 ⊢ ((((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) ∧ (𝐹‘𝑥) = (𝐹‘𝑦)) ∧ ((𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴) ∧ (𝐹‘𝑦) = (𝐹‘𝑧))) → (𝐹‘𝑥) = (𝐹‘𝑧))
25	20, 21, 24	jca31 524	. . . 4 ⊢ ((((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) ∧ (𝐹‘𝑥) = (𝐹‘𝑦)) ∧ ((𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴) ∧ (𝐹‘𝑦) = (𝐹‘𝑧))) → ((𝑥 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴) ∧ (𝐹‘𝑥) = (𝐹‘𝑧)))
26		simpl 488	. . . . . . . 8 ⊢ ((𝑢 = 𝑦 ∧ 𝑣 = 𝑧) → 𝑢 = 𝑦)
27	26	fveq2d 6889	. . . . . . 7 ⊢ ((𝑢 = 𝑦 ∧ 𝑣 = 𝑧) → (𝐹‘𝑢) = (𝐹‘𝑦))
28		simpr 490	. . . . . . . 8 ⊢ ((𝑢 = 𝑦 ∧ 𝑣 = 𝑧) → 𝑣 = 𝑧)
29	28	fveq2d 6889	. . . . . . 7 ⊢ ((𝑢 = 𝑦 ∧ 𝑣 = 𝑧) → (𝐹‘𝑣) = (𝐹‘𝑧))
30	27, 29	eqeq12d 2776	. . . . . 6 ⊢ ((𝑢 = 𝑦 ∧ 𝑣 = 𝑧) → ((𝐹‘𝑢) = (𝐹‘𝑣) ↔ (𝐹‘𝑦) = (𝐹‘𝑧)))
31	30, 10	brab2a 5743	. . . . 5 ⊢ (𝑦{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑧 ↔ ((𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴) ∧ (𝐹‘𝑦) = (𝐹‘𝑧)))
32	11, 31	anbi12i 640	. . . 4 ⊢ ((𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑦 ∧ 𝑦{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑧) ↔ (((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) ∧ (𝐹‘𝑥) = (𝐹‘𝑦)) ∧ ((𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴) ∧ (𝐹‘𝑦) = (𝐹‘𝑧))))
33		simpl 488	. . . . . . 7 ⊢ ((𝑢 = 𝑥 ∧ 𝑣 = 𝑧) → 𝑢 = 𝑥)
34	33	fveq2d 6889	. . . . . 6 ⊢ ((𝑢 = 𝑥 ∧ 𝑣 = 𝑧) → (𝐹‘𝑢) = (𝐹‘𝑥))
35		simpr 490	. . . . . . 7 ⊢ ((𝑢 = 𝑥 ∧ 𝑣 = 𝑧) → 𝑣 = 𝑧)
36	35	fveq2d 6889	. . . . . 6 ⊢ ((𝑢 = 𝑥 ∧ 𝑣 = 𝑧) → (𝐹‘𝑣) = (𝐹‘𝑧))
37	34, 36	eqeq12d 2776	. . . . 5 ⊢ ((𝑢 = 𝑥 ∧ 𝑣 = 𝑧) → ((𝐹‘𝑢) = (𝐹‘𝑣) ↔ (𝐹‘𝑥) = (𝐹‘𝑧)))
38	37, 10	brab2a 5743	. . . 4 ⊢ (𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑧 ↔ ((𝑥 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴) ∧ (𝐹‘𝑥) = (𝐹‘𝑧)))
39	25, 32, 38	3imtr4i 295	. . 3 ⊢ ((𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑦 ∧ 𝑦{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑧) → 𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑧)
40		eqid 2760	. . . . 5 ⊢ (𝐹‘𝑥) = (𝐹‘𝑥)
41	40	biantru 539	. . . 4 ⊢ ((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐴) ↔ ((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐴) ∧ (𝐹‘𝑥) = (𝐹‘𝑥)))
42		pm4.24 574	. . . 4 ⊢ (𝑥 ∈ 𝐴 ↔ (𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐴))
43		simpl 488	. . . . . . 7 ⊢ ((𝑢 = 𝑥 ∧ 𝑣 = 𝑥) → 𝑢 = 𝑥)
44	43	fveq2d 6889	. . . . . 6 ⊢ ((𝑢 = 𝑥 ∧ 𝑣 = 𝑥) → (𝐹‘𝑢) = (𝐹‘𝑥))
45		simpr 490	. . . . . . 7 ⊢ ((𝑢 = 𝑥 ∧ 𝑣 = 𝑥) → 𝑣 = 𝑥)
46	45	fveq2d 6889	. . . . . 6 ⊢ ((𝑢 = 𝑥 ∧ 𝑣 = 𝑥) → (𝐹‘𝑣) = (𝐹‘𝑥))
47	44, 46	eqeq12d 2776	. . . . 5 ⊢ ((𝑢 = 𝑥 ∧ 𝑣 = 𝑥) → ((𝐹‘𝑢) = (𝐹‘𝑣) ↔ (𝐹‘𝑥) = (𝐹‘𝑥)))
48	47, 10	brab2a 5743	. . . 4 ⊢ (𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑥 ↔ ((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐴) ∧ (𝐹‘𝑥) = (𝐹‘𝑥)))
49	41, 42, 48	3bitr4i 306	. . 3 ⊢ (𝑥 ∈ 𝐴 ↔ 𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑥)
50	1, 19, 39, 49	iseri 8745	. 2 ⊢ {⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))} Er 𝐴
51	11	baib 545	. . 3 ⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) → (𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑦 ↔ (𝐹‘𝑥) = (𝐹‘𝑦)))
52	51	rgen2 3202	. 2 ⊢ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑦 ↔ (𝐹‘𝑥) = (𝐹‘𝑦))
53		id 23	. . . 4 ⊢ (𝐴 ∈ 𝑉 → 𝐴 ∈ 𝑉)
54		simprll 791	. . . 4 ⊢ ((𝐴 ∈ 𝑉 ∧ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))) → 𝑢 ∈ 𝐴)
55		simprlr 792	. . . 4 ⊢ ((𝐴 ∈ 𝑉 ∧ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))) → 𝑣 ∈ 𝐴)
56	53, 53, 54, 55	opabex2 8068	. . 3 ⊢ (𝐴 ∈ 𝑉 → {⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))} ∈ V)
57		ereq1 8725	. . . . 5 ⊢ (𝑟 = {⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))} → (𝑟 Er 𝐴 ↔ {⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))} Er 𝐴))
58		simpl 488	. . . . . . . 8 ⊢ ((𝑟 = {⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))} ∧ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴)) → 𝑟 = {⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))})
59	58	breqd 5113	. . . . . . 7 ⊢ ((𝑟 = {⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))} ∧ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴)) → (𝑥𝑟𝑦 ↔ 𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑦))
60	59	bibi1d 346	. . . . . 6 ⊢ ((𝑟 = {⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))} ∧ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴)) → ((𝑥𝑟𝑦 ↔ (𝐹‘𝑥) = (𝐹‘𝑦)) ↔ (𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑦 ↔ (𝐹‘𝑥) = (𝐹‘𝑦))))
61	60	2ralbidva 3224	. . . . 5 ⊢ (𝑟 = {⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))} → (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥𝑟𝑦 ↔ (𝐹‘𝑥) = (𝐹‘𝑦)) ↔ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑦 ↔ (𝐹‘𝑥) = (𝐹‘𝑦))))
62	57, 61	anbi12d 644	. . . 4 ⊢ (𝑟 = {⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))} → ((𝑟 Er 𝐴 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥𝑟𝑦 ↔ (𝐹‘𝑥) = (𝐹‘𝑦))) ↔ ({⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))} Er 𝐴 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑦 ↔ (𝐹‘𝑥) = (𝐹‘𝑦)))))
63	62	spcegv 3551	. . 3 ⊢ ({⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))} ∈ V → (({⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))} Er 𝐴 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑦 ↔ (𝐹‘𝑥) = (𝐹‘𝑦))) → ∃𝑟(𝑟 Er 𝐴 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥𝑟𝑦 ↔ (𝐹‘𝑥) = (𝐹‘𝑦)))))
64	56, 63	syl 18	. 2 ⊢ (𝐴 ∈ 𝑉 → (({⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))} Er 𝐴 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥{⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) ∧ (𝐹‘𝑢) = (𝐹‘𝑣))}𝑦 ↔ (𝐹‘𝑥) = (𝐹‘𝑦))) → ∃𝑟(𝑟 Er 𝐴 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥𝑟𝑦 ↔ (𝐹‘𝑥) = (𝐹‘𝑦)))))
65	50, 52, 64	mp2ani 711	1 ⊢ (𝐴 ∈ 𝑉 → ∃𝑟(𝑟 Er 𝐴 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥𝑟𝑦 ↔ (𝐹‘𝑥) = (𝐹‘𝑦))))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401   = wceq 1569  ∃wex 1811   ∈ wcel 2144  ∀wral 3076  Vcvv 3450   class class class wbr 5102  {copab 5166  ‘cfv 6538   Er wer 8714

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1827  ax-4 1841  ax-5 1942  ax-6 1999  ax-7 2040  ax-8 2146  ax-9 2154  ax-ext 2732  ax-sep 5248  ax-pow 5326  ax-pr 5390  ax-un 7751

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1572  df-fal 1582  df-ex 1812  df-sb 2099  df-clab 2739  df-cleq 2752  df-clel 2835  df-ral 3077  df-rex 3087  df-rab 3413  df-v 3452  df-ss 3896  df-dif 4047  df-in 4091  df-un 4151  df-nul 4279  df-if 4482  df-pw 4558  df-sn 4584  df-pr 4586  df-op 4590  df-uni 4867  df-br 5103  df-opab 5167  df-xp 5656  df-rel 5657  df-cnv 5658  df-co 5659  df-dm 5660  df-iota 6494  df-fv 6546  df-er 8717

This theorem is used by:  tgjustc1  28937