Step |
Hyp |
Ref |
Expression |
1 |
|
ralxpxfr2d.a |
⊢ 𝐴 ∈ V |
2 |
|
ralxpxfr2d.b |
⊢ ( 𝜑 → ( 𝑥 ∈ 𝐵 ↔ ∃ 𝑦 ∈ 𝐶 ∃ 𝑧 ∈ 𝐷 𝑥 = 𝐴 ) ) |
3 |
|
ralxpxfr2d.c |
⊢ ( ( 𝜑 ∧ 𝑥 = 𝐴 ) → ( 𝜓 ↔ 𝜒 ) ) |
4 |
|
df-ral |
⊢ ( ∀ 𝑥 ∈ 𝐵 𝜓 ↔ ∀ 𝑥 ( 𝑥 ∈ 𝐵 → 𝜓 ) ) |
5 |
2
|
imbi1d |
⊢ ( 𝜑 → ( ( 𝑥 ∈ 𝐵 → 𝜓 ) ↔ ( ∃ 𝑦 ∈ 𝐶 ∃ 𝑧 ∈ 𝐷 𝑥 = 𝐴 → 𝜓 ) ) ) |
6 |
5
|
albidv |
⊢ ( 𝜑 → ( ∀ 𝑥 ( 𝑥 ∈ 𝐵 → 𝜓 ) ↔ ∀ 𝑥 ( ∃ 𝑦 ∈ 𝐶 ∃ 𝑧 ∈ 𝐷 𝑥 = 𝐴 → 𝜓 ) ) ) |
7 |
4 6
|
syl5bb |
⊢ ( 𝜑 → ( ∀ 𝑥 ∈ 𝐵 𝜓 ↔ ∀ 𝑥 ( ∃ 𝑦 ∈ 𝐶 ∃ 𝑧 ∈ 𝐷 𝑥 = 𝐴 → 𝜓 ) ) ) |
8 |
|
ralcom4 |
⊢ ( ∀ 𝑦 ∈ 𝐶 ∀ 𝑥 ∀ 𝑧 ∈ 𝐷 ( 𝑥 = 𝐴 → 𝜓 ) ↔ ∀ 𝑥 ∀ 𝑦 ∈ 𝐶 ∀ 𝑧 ∈ 𝐷 ( 𝑥 = 𝐴 → 𝜓 ) ) |
9 |
|
ralcom4 |
⊢ ( ∀ 𝑧 ∈ 𝐷 ∀ 𝑥 ( 𝑥 = 𝐴 → 𝜓 ) ↔ ∀ 𝑥 ∀ 𝑧 ∈ 𝐷 ( 𝑥 = 𝐴 → 𝜓 ) ) |
10 |
9
|
ralbii |
⊢ ( ∀ 𝑦 ∈ 𝐶 ∀ 𝑧 ∈ 𝐷 ∀ 𝑥 ( 𝑥 = 𝐴 → 𝜓 ) ↔ ∀ 𝑦 ∈ 𝐶 ∀ 𝑥 ∀ 𝑧 ∈ 𝐷 ( 𝑥 = 𝐴 → 𝜓 ) ) |
11 |
|
r19.23v |
⊢ ( ∀ 𝑧 ∈ 𝐷 ( 𝑥 = 𝐴 → 𝜓 ) ↔ ( ∃ 𝑧 ∈ 𝐷 𝑥 = 𝐴 → 𝜓 ) ) |
12 |
11
|
ralbii |
⊢ ( ∀ 𝑦 ∈ 𝐶 ∀ 𝑧 ∈ 𝐷 ( 𝑥 = 𝐴 → 𝜓 ) ↔ ∀ 𝑦 ∈ 𝐶 ( ∃ 𝑧 ∈ 𝐷 𝑥 = 𝐴 → 𝜓 ) ) |
13 |
|
r19.23v |
⊢ ( ∀ 𝑦 ∈ 𝐶 ( ∃ 𝑧 ∈ 𝐷 𝑥 = 𝐴 → 𝜓 ) ↔ ( ∃ 𝑦 ∈ 𝐶 ∃ 𝑧 ∈ 𝐷 𝑥 = 𝐴 → 𝜓 ) ) |
14 |
12 13
|
bitr2i |
⊢ ( ( ∃ 𝑦 ∈ 𝐶 ∃ 𝑧 ∈ 𝐷 𝑥 = 𝐴 → 𝜓 ) ↔ ∀ 𝑦 ∈ 𝐶 ∀ 𝑧 ∈ 𝐷 ( 𝑥 = 𝐴 → 𝜓 ) ) |
15 |
14
|
albii |
⊢ ( ∀ 𝑥 ( ∃ 𝑦 ∈ 𝐶 ∃ 𝑧 ∈ 𝐷 𝑥 = 𝐴 → 𝜓 ) ↔ ∀ 𝑥 ∀ 𝑦 ∈ 𝐶 ∀ 𝑧 ∈ 𝐷 ( 𝑥 = 𝐴 → 𝜓 ) ) |
16 |
8 10 15
|
3bitr4ri |
⊢ ( ∀ 𝑥 ( ∃ 𝑦 ∈ 𝐶 ∃ 𝑧 ∈ 𝐷 𝑥 = 𝐴 → 𝜓 ) ↔ ∀ 𝑦 ∈ 𝐶 ∀ 𝑧 ∈ 𝐷 ∀ 𝑥 ( 𝑥 = 𝐴 → 𝜓 ) ) |
17 |
7 16
|
bitrdi |
⊢ ( 𝜑 → ( ∀ 𝑥 ∈ 𝐵 𝜓 ↔ ∀ 𝑦 ∈ 𝐶 ∀ 𝑧 ∈ 𝐷 ∀ 𝑥 ( 𝑥 = 𝐴 → 𝜓 ) ) ) |
18 |
3
|
pm5.74da |
⊢ ( 𝜑 → ( ( 𝑥 = 𝐴 → 𝜓 ) ↔ ( 𝑥 = 𝐴 → 𝜒 ) ) ) |
19 |
18
|
albidv |
⊢ ( 𝜑 → ( ∀ 𝑥 ( 𝑥 = 𝐴 → 𝜓 ) ↔ ∀ 𝑥 ( 𝑥 = 𝐴 → 𝜒 ) ) ) |
20 |
|
biidd |
⊢ ( 𝑥 = 𝐴 → ( 𝜒 ↔ 𝜒 ) ) |
21 |
1 20
|
ceqsalv |
⊢ ( ∀ 𝑥 ( 𝑥 = 𝐴 → 𝜒 ) ↔ 𝜒 ) |
22 |
19 21
|
bitrdi |
⊢ ( 𝜑 → ( ∀ 𝑥 ( 𝑥 = 𝐴 → 𝜓 ) ↔ 𝜒 ) ) |
23 |
22
|
2ralbidv |
⊢ ( 𝜑 → ( ∀ 𝑦 ∈ 𝐶 ∀ 𝑧 ∈ 𝐷 ∀ 𝑥 ( 𝑥 = 𝐴 → 𝜓 ) ↔ ∀ 𝑦 ∈ 𝐶 ∀ 𝑧 ∈ 𝐷 𝜒 ) ) |
24 |
17 23
|
bitrd |
⊢ ( 𝜑 → ( ∀ 𝑥 ∈ 𝐵 𝜓 ↔ ∀ 𝑦 ∈ 𝐶 ∀ 𝑧 ∈ 𝐷 𝜒 ) ) |