Metamath Proof Explorer


Theorem noinfcbv

Description: Change bound variables for surreal infimum. (Contributed by Scott Fenton, 9-Aug-2024)

Ref Expression
Hypothesis noinfcbv.1 ⊢ T = if ∃ x ∈ B ∀ y ∈ B ¬ y < s x ι x ∈ B | ∀ y ∈ B ¬ y < s x ∪ dom ⁡ ι x ∈ B | ∀ y ∈ B ¬ y < s x 1 𝑜 g ∈ y | ∃ u ∈ B y ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ y = v ↾ suc ⁡ y ⟼ ι x | ∃ u ∈ B g ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ g = v ↾ suc ⁡ g ∧ u ⁡ g = x
Assertion noinfcbv ⊢ T = if ∃ a ∈ B ∀ b ∈ B ¬ b < s a ι a ∈ B | ∀ b ∈ B ¬ b < s a ∪ dom ⁡ ι a ∈ B | ∀ b ∈ B ¬ b < s a 1 𝑜 c ∈ b | ∃ d ∈ B b ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ b = e ↾ suc ⁡ b ⟼ ι a | ∃ d ∈ B c ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ c = e ↾ suc ⁡ c ∧ d ⁡ c = a

Proof

Step Hyp Ref Expression
1 noinfcbv.1 ⊢ T = if ∃ x ∈ B ∀ y ∈ B ¬ y < s x ι x ∈ B | ∀ y ∈ B ¬ y < s x ∪ dom ⁡ ι x ∈ B | ∀ y ∈ B ¬ y < s x 1 𝑜 g ∈ y | ∃ u ∈ B y ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ y = v ↾ suc ⁡ y ⟼ ι x | ∃ u ∈ B g ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ g = v ↾ suc ⁡ g ∧ u ⁡ g = x
2 breq2 ⊢ x = a → y < s x ↔ y < s a
3 2 notbid ⊢ x = a → ¬ y < s x ↔ ¬ y < s a
4 3 ralbidv ⊢ x = a → ∀ y ∈ B ¬ y < s x ↔ ∀ y ∈ B ¬ y < s a
5 breq1 ⊢ y = b → y < s a ↔ b < s a
6 5 notbid ⊢ y = b → ¬ y < s a ↔ ¬ b < s a
7 6 cbvralvw ⊢ ∀ y ∈ B ¬ y < s a ↔ ∀ b ∈ B ¬ b < s a
8 4 7 bitrdi ⊢ x = a → ∀ y ∈ B ¬ y < s x ↔ ∀ b ∈ B ¬ b < s a
9 8 cbvrexvw ⊢ ∃ x ∈ B ∀ y ∈ B ¬ y < s x ↔ ∃ a ∈ B ∀ b ∈ B ¬ b < s a
10 8 cbvriotavw ⊢ ι x ∈ B | ∀ y ∈ B ¬ y < s x = ι a ∈ B | ∀ b ∈ B ¬ b < s a
11 10 dmeqi ⊢ dom ⁡ ι x ∈ B | ∀ y ∈ B ¬ y < s x = dom ⁡ ι a ∈ B | ∀ b ∈ B ¬ b < s a
12 11 opeq1i ⊢ dom ⁡ ι x ∈ B | ∀ y ∈ B ¬ y < s x 1 𝑜 = dom ⁡ ι a ∈ B | ∀ b ∈ B ¬ b < s a 1 𝑜
13 12 sneqi ⊢ dom ⁡ ι x ∈ B | ∀ y ∈ B ¬ y < s x 1 𝑜 = dom ⁡ ι a ∈ B | ∀ b ∈ B ¬ b < s a 1 𝑜
14 10 13 uneq12i ⊢ ι x ∈ B | ∀ y ∈ B ¬ y < s x ∪ dom ⁡ ι x ∈ B | ∀ y ∈ B ¬ y < s x 1 𝑜 = ι a ∈ B | ∀ b ∈ B ¬ b < s a ∪ dom ⁡ ι a ∈ B | ∀ b ∈ B ¬ b < s a 1 𝑜
15 eleq1w ⊢ g = c → g ∈ dom ⁡ u ↔ c ∈ dom ⁡ u
16 suceq ⊢ g = c → suc ⁡ g = suc ⁡ c
17 16 reseq2d ⊢ g = c → u ↾ suc ⁡ g = u ↾ suc ⁡ c
18 16 reseq2d ⊢ g = c → v ↾ suc ⁡ g = v ↾ suc ⁡ c
19 17 18 eqeq12d ⊢ g = c → u ↾ suc ⁡ g = v ↾ suc ⁡ g ↔ u ↾ suc ⁡ c = v ↾ suc ⁡ c
20 19 imbi2d ⊢ g = c → ¬ u < s v → u ↾ suc ⁡ g = v ↾ suc ⁡ g ↔ ¬ u < s v → u ↾ suc ⁡ c = v ↾ suc ⁡ c
21 20 ralbidv ⊢ g = c → ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ g = v ↾ suc ⁡ g ↔ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ c = v ↾ suc ⁡ c
22 fveqeq2 ⊢ g = c → u ⁡ g = x ↔ u ⁡ c = x
23 15 21 22 3anbi123d ⊢ g = c → g ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ g = v ↾ suc ⁡ g ∧ u ⁡ g = x ↔ c ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ c = v ↾ suc ⁡ c ∧ u ⁡ c = x
24 23 rexbidv ⊢ g = c → ∃ u ∈ B g ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ g = v ↾ suc ⁡ g ∧ u ⁡ g = x ↔ ∃ u ∈ B c ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ c = v ↾ suc ⁡ c ∧ u ⁡ c = x
25 24 iotabidv ⊢ g = c → ι x | ∃ u ∈ B g ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ g = v ↾ suc ⁡ g ∧ u ⁡ g = x = ι x | ∃ u ∈ B c ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ c = v ↾ suc ⁡ c ∧ u ⁡ c = x
26 eqeq2 ⊢ x = a → u ⁡ c = x ↔ u ⁡ c = a
27 26 3anbi3d ⊢ x = a → c ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ c = v ↾ suc ⁡ c ∧ u ⁡ c = x ↔ c ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ c = v ↾ suc ⁡ c ∧ u ⁡ c = a
28 27 rexbidv ⊢ x = a → ∃ u ∈ B c ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ c = v ↾ suc ⁡ c ∧ u ⁡ c = x ↔ ∃ u ∈ B c ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ c = v ↾ suc ⁡ c ∧ u ⁡ c = a
29 dmeq ⊢ u = d → dom ⁡ u = dom ⁡ d
30 29 eleq2d ⊢ u = d → c ∈ dom ⁡ u ↔ c ∈ dom ⁡ d
31 breq1 ⊢ u = d → u < s v ↔ d < s v
32 31 notbid ⊢ u = d → ¬ u < s v ↔ ¬ d < s v
33 reseq1 ⊢ u = d → u ↾ suc ⁡ c = d ↾ suc ⁡ c
34 33 eqeq1d ⊢ u = d → u ↾ suc ⁡ c = v ↾ suc ⁡ c ↔ d ↾ suc ⁡ c = v ↾ suc ⁡ c
35 32 34 imbi12d ⊢ u = d → ¬ u < s v → u ↾ suc ⁡ c = v ↾ suc ⁡ c ↔ ¬ d < s v → d ↾ suc ⁡ c = v ↾ suc ⁡ c
36 35 ralbidv ⊢ u = d → ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ c = v ↾ suc ⁡ c ↔ ∀ v ∈ B ¬ d < s v → d ↾ suc ⁡ c = v ↾ suc ⁡ c
37 breq2 ⊢ v = e → d < s v ↔ d < s e
38 37 notbid ⊢ v = e → ¬ d < s v ↔ ¬ d < s e
39 reseq1 ⊢ v = e → v ↾ suc ⁡ c = e ↾ suc ⁡ c
40 39 eqeq2d ⊢ v = e → d ↾ suc ⁡ c = v ↾ suc ⁡ c ↔ d ↾ suc ⁡ c = e ↾ suc ⁡ c
41 38 40 imbi12d ⊢ v = e → ¬ d < s v → d ↾ suc ⁡ c = v ↾ suc ⁡ c ↔ ¬ d < s e → d ↾ suc ⁡ c = e ↾ suc ⁡ c
42 41 cbvralvw ⊢ ∀ v ∈ B ¬ d < s v → d ↾ suc ⁡ c = v ↾ suc ⁡ c ↔ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ c = e ↾ suc ⁡ c
43 36 42 bitrdi ⊢ u = d → ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ c = v ↾ suc ⁡ c ↔ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ c = e ↾ suc ⁡ c
44 fveq1 ⊢ u = d → u ⁡ c = d ⁡ c
45 44 eqeq1d ⊢ u = d → u ⁡ c = a ↔ d ⁡ c = a
46 30 43 45 3anbi123d ⊢ u = d → c ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ c = v ↾ suc ⁡ c ∧ u ⁡ c = a ↔ c ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ c = e ↾ suc ⁡ c ∧ d ⁡ c = a
47 46 cbvrexvw ⊢ ∃ u ∈ B c ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ c = v ↾ suc ⁡ c ∧ u ⁡ c = a ↔ ∃ d ∈ B c ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ c = e ↾ suc ⁡ c ∧ d ⁡ c = a
48 28 47 bitrdi ⊢ x = a → ∃ u ∈ B c ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ c = v ↾ suc ⁡ c ∧ u ⁡ c = x ↔ ∃ d ∈ B c ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ c = e ↾ suc ⁡ c ∧ d ⁡ c = a
49 48 cbviotavw ⊢ ι x | ∃ u ∈ B c ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ c = v ↾ suc ⁡ c ∧ u ⁡ c = x = ι a | ∃ d ∈ B c ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ c = e ↾ suc ⁡ c ∧ d ⁡ c = a
50 25 49 eqtrdi ⊢ g = c → ι x | ∃ u ∈ B g ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ g = v ↾ suc ⁡ g ∧ u ⁡ g = x = ι a | ∃ d ∈ B c ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ c = e ↾ suc ⁡ c ∧ d ⁡ c = a
51 50 cbvmptv ⊢ g ∈ y | ∃ u ∈ B y ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ y = v ↾ suc ⁡ y ⟼ ι x | ∃ u ∈ B g ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ g = v ↾ suc ⁡ g ∧ u ⁡ g = x = c ∈ y | ∃ u ∈ B y ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ y = v ↾ suc ⁡ y ⟼ ι a | ∃ d ∈ B c ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ c = e ↾ suc ⁡ c ∧ d ⁡ c = a
52 eleq1w ⊢ y = b → y ∈ dom ⁡ u ↔ b ∈ dom ⁡ u
53 suceq ⊢ y = b → suc ⁡ y = suc ⁡ b
54 53 reseq2d ⊢ y = b → u ↾ suc ⁡ y = u ↾ suc ⁡ b
55 53 reseq2d ⊢ y = b → v ↾ suc ⁡ y = v ↾ suc ⁡ b
56 54 55 eqeq12d ⊢ y = b → u ↾ suc ⁡ y = v ↾ suc ⁡ y ↔ u ↾ suc ⁡ b = v ↾ suc ⁡ b
57 56 imbi2d ⊢ y = b → ¬ u < s v → u ↾ suc ⁡ y = v ↾ suc ⁡ y ↔ ¬ u < s v → u ↾ suc ⁡ b = v ↾ suc ⁡ b
58 57 ralbidv ⊢ y = b → ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ y = v ↾ suc ⁡ y ↔ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ b = v ↾ suc ⁡ b
59 52 58 anbi12d ⊢ y = b → y ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ y = v ↾ suc ⁡ y ↔ b ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ b = v ↾ suc ⁡ b
60 59 rexbidv ⊢ y = b → ∃ u ∈ B y ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ y = v ↾ suc ⁡ y ↔ ∃ u ∈ B b ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ b = v ↾ suc ⁡ b
61 29 eleq2d ⊢ u = d → b ∈ dom ⁡ u ↔ b ∈ dom ⁡ d
62 reseq1 ⊢ u = d → u ↾ suc ⁡ b = d ↾ suc ⁡ b
63 62 eqeq1d ⊢ u = d → u ↾ suc ⁡ b = v ↾ suc ⁡ b ↔ d ↾ suc ⁡ b = v ↾ suc ⁡ b
64 32 63 imbi12d ⊢ u = d → ¬ u < s v → u ↾ suc ⁡ b = v ↾ suc ⁡ b ↔ ¬ d < s v → d ↾ suc ⁡ b = v ↾ suc ⁡ b
65 64 ralbidv ⊢ u = d → ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ b = v ↾ suc ⁡ b ↔ ∀ v ∈ B ¬ d < s v → d ↾ suc ⁡ b = v ↾ suc ⁡ b
66 reseq1 ⊢ v = e → v ↾ suc ⁡ b = e ↾ suc ⁡ b
67 66 eqeq2d ⊢ v = e → d ↾ suc ⁡ b = v ↾ suc ⁡ b ↔ d ↾ suc ⁡ b = e ↾ suc ⁡ b
68 38 67 imbi12d ⊢ v = e → ¬ d < s v → d ↾ suc ⁡ b = v ↾ suc ⁡ b ↔ ¬ d < s e → d ↾ suc ⁡ b = e ↾ suc ⁡ b
69 68 cbvralvw ⊢ ∀ v ∈ B ¬ d < s v → d ↾ suc ⁡ b = v ↾ suc ⁡ b ↔ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ b = e ↾ suc ⁡ b
70 65 69 bitrdi ⊢ u = d → ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ b = v ↾ suc ⁡ b ↔ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ b = e ↾ suc ⁡ b
71 61 70 anbi12d ⊢ u = d → b ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ b = v ↾ suc ⁡ b ↔ b ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ b = e ↾ suc ⁡ b
72 71 cbvrexvw ⊢ ∃ u ∈ B b ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ b = v ↾ suc ⁡ b ↔ ∃ d ∈ B b ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ b = e ↾ suc ⁡ b
73 60 72 bitrdi ⊢ y = b → ∃ u ∈ B y ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ y = v ↾ suc ⁡ y ↔ ∃ d ∈ B b ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ b = e ↾ suc ⁡ b
74 73 cbvabv ⊢ y | ∃ u ∈ B y ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ y = v ↾ suc ⁡ y = b | ∃ d ∈ B b ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ b = e ↾ suc ⁡ b
75 74 mpteq1i ⊢ c ∈ y | ∃ u ∈ B y ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ y = v ↾ suc ⁡ y ⟼ ι a | ∃ d ∈ B c ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ c = e ↾ suc ⁡ c ∧ d ⁡ c = a = c ∈ b | ∃ d ∈ B b ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ b = e ↾ suc ⁡ b ⟼ ι a | ∃ d ∈ B c ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ c = e ↾ suc ⁡ c ∧ d ⁡ c = a
76 51 75 eqtri ⊢ g ∈ y | ∃ u ∈ B y ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ y = v ↾ suc ⁡ y ⟼ ι x | ∃ u ∈ B g ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ g = v ↾ suc ⁡ g ∧ u ⁡ g = x = c ∈ b | ∃ d ∈ B b ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ b = e ↾ suc ⁡ b ⟼ ι a | ∃ d ∈ B c ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ c = e ↾ suc ⁡ c ∧ d ⁡ c = a
77 9 14 76 ifbieq12i ⊢ if ∃ x ∈ B ∀ y ∈ B ¬ y < s x ι x ∈ B | ∀ y ∈ B ¬ y < s x ∪ dom ⁡ ι x ∈ B | ∀ y ∈ B ¬ y < s x 1 𝑜 g ∈ y | ∃ u ∈ B y ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ y = v ↾ suc ⁡ y ⟼ ι x | ∃ u ∈ B g ∈ dom ⁡ u ∧ ∀ v ∈ B ¬ u < s v → u ↾ suc ⁡ g = v ↾ suc ⁡ g ∧ u ⁡ g = x = if ∃ a ∈ B ∀ b ∈ B ¬ b < s a ι a ∈ B | ∀ b ∈ B ¬ b < s a ∪ dom ⁡ ι a ∈ B | ∀ b ∈ B ¬ b < s a 1 𝑜 c ∈ b | ∃ d ∈ B b ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ b = e ↾ suc ⁡ b ⟼ ι a | ∃ d ∈ B c ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ c = e ↾ suc ⁡ c ∧ d ⁡ c = a
78 1 77 eqtri ⊢ T = if ∃ a ∈ B ∀ b ∈ B ¬ b < s a ι a ∈ B | ∀ b ∈ B ¬ b < s a ∪ dom ⁡ ι a ∈ B | ∀ b ∈ B ¬ b < s a 1 𝑜 c ∈ b | ∃ d ∈ B b ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ b = e ↾ suc ⁡ b ⟼ ι a | ∃ d ∈ B c ∈ dom ⁡ d ∧ ∀ e ∈ B ¬ d < s e → d ↾ suc ⁡ c = e ↾ suc ⁡ c ∧ d ⁡ c = a