Step |
Hyp |
Ref |
Expression |
1 |
|
idn1 |
⊢ ( 𝐴 ∈ 𝑉 ▶ 𝐴 ∈ 𝑉 ) |
2 |
|
sbceqg |
⊢ ( 𝐴 ∈ 𝑉 → ( [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 ↔ ⦋ 𝐴 / 𝑥 ⦌ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ) ) |
3 |
1 2
|
e1a |
⊢ ( 𝐴 ∈ 𝑉 ▶ ( [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 ↔ ⦋ 𝐴 / 𝑥 ⦌ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ) ) |
4 |
|
csbconstg |
⊢ ( 𝐴 ∈ 𝑉 → ⦋ 𝐴 / 𝑥 ⦌ 𝑦 = 𝑦 ) |
5 |
1 4
|
e1a |
⊢ ( 𝐴 ∈ 𝑉 ▶ ⦋ 𝐴 / 𝑥 ⦌ 𝑦 = 𝑦 ) |
6 |
|
eqeq1 |
⊢ ( ⦋ 𝐴 / 𝑥 ⦌ 𝑦 = 𝑦 → ( ⦋ 𝐴 / 𝑥 ⦌ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ↔ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ) ) |
7 |
5 6
|
e1a |
⊢ ( 𝐴 ∈ 𝑉 ▶ ( ⦋ 𝐴 / 𝑥 ⦌ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ↔ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ) ) |
8 |
|
bibi1 |
⊢ ( ( [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 ↔ ⦋ 𝐴 / 𝑥 ⦌ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ) → ( ( [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 ↔ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ) ↔ ( ⦋ 𝐴 / 𝑥 ⦌ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ↔ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ) ) ) |
9 |
8
|
biimprd |
⊢ ( ( [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 ↔ ⦋ 𝐴 / 𝑥 ⦌ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ) → ( ( ⦋ 𝐴 / 𝑥 ⦌ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ↔ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ) → ( [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 ↔ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ) ) ) |
10 |
3 7 9
|
e11 |
⊢ ( 𝐴 ∈ 𝑉 ▶ ( [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 ↔ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ) ) |
11 |
10
|
gen11 |
⊢ ( 𝐴 ∈ 𝑉 ▶ ∀ 𝑦 ( [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 ↔ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ) ) |
12 |
|
abbi |
⊢ ( ∀ 𝑦 ( [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 ↔ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ) ↔ { 𝑦 ∣ [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } ) |
13 |
12
|
biimpi |
⊢ ( ∀ 𝑦 ( [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 ↔ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 ) → { 𝑦 ∣ [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } ) |
14 |
11 13
|
e1a |
⊢ ( 𝐴 ∈ 𝑉 ▶ { 𝑦 ∣ [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } ) |
15 |
|
csbab |
⊢ ⦋ 𝐴 / 𝑥 ⦌ { 𝑦 ∣ 𝑦 = 𝐵 } = { 𝑦 ∣ [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 } |
16 |
15
|
a1i |
⊢ ( 𝐴 ∈ 𝑉 → ⦋ 𝐴 / 𝑥 ⦌ { 𝑦 ∣ 𝑦 = 𝐵 } = { 𝑦 ∣ [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 } ) |
17 |
16
|
eqcomd |
⊢ ( 𝐴 ∈ 𝑉 → { 𝑦 ∣ [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 } = ⦋ 𝐴 / 𝑥 ⦌ { 𝑦 ∣ 𝑦 = 𝐵 } ) |
18 |
1 17
|
e1a |
⊢ ( 𝐴 ∈ 𝑉 ▶ { 𝑦 ∣ [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 } = ⦋ 𝐴 / 𝑥 ⦌ { 𝑦 ∣ 𝑦 = 𝐵 } ) |
19 |
|
eqeq1 |
⊢ ( { 𝑦 ∣ [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 } = ⦋ 𝐴 / 𝑥 ⦌ { 𝑦 ∣ 𝑦 = 𝐵 } → ( { 𝑦 ∣ [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } ↔ ⦋ 𝐴 / 𝑥 ⦌ { 𝑦 ∣ 𝑦 = 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } ) ) |
20 |
19
|
biimpcd |
⊢ ( { 𝑦 ∣ [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } → ( { 𝑦 ∣ [ 𝐴 / 𝑥 ] 𝑦 = 𝐵 } = ⦋ 𝐴 / 𝑥 ⦌ { 𝑦 ∣ 𝑦 = 𝐵 } → ⦋ 𝐴 / 𝑥 ⦌ { 𝑦 ∣ 𝑦 = 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } ) ) |
21 |
14 18 20
|
e11 |
⊢ ( 𝐴 ∈ 𝑉 ▶ ⦋ 𝐴 / 𝑥 ⦌ { 𝑦 ∣ 𝑦 = 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } ) |
22 |
|
df-sn |
⊢ { 𝐵 } = { 𝑦 ∣ 𝑦 = 𝐵 } |
23 |
22
|
ax-gen |
⊢ ∀ 𝑥 { 𝐵 } = { 𝑦 ∣ 𝑦 = 𝐵 } |
24 |
|
csbeq2 |
⊢ ( ∀ 𝑥 { 𝐵 } = { 𝑦 ∣ 𝑦 = 𝐵 } → ⦋ 𝐴 / 𝑥 ⦌ { 𝐵 } = ⦋ 𝐴 / 𝑥 ⦌ { 𝑦 ∣ 𝑦 = 𝐵 } ) |
25 |
24
|
a1i |
⊢ ( 𝐴 ∈ 𝑉 → ( ∀ 𝑥 { 𝐵 } = { 𝑦 ∣ 𝑦 = 𝐵 } → ⦋ 𝐴 / 𝑥 ⦌ { 𝐵 } = ⦋ 𝐴 / 𝑥 ⦌ { 𝑦 ∣ 𝑦 = 𝐵 } ) ) |
26 |
1 23 25
|
e10 |
⊢ ( 𝐴 ∈ 𝑉 ▶ ⦋ 𝐴 / 𝑥 ⦌ { 𝐵 } = ⦋ 𝐴 / 𝑥 ⦌ { 𝑦 ∣ 𝑦 = 𝐵 } ) |
27 |
|
eqeq2 |
⊢ ( ⦋ 𝐴 / 𝑥 ⦌ { 𝑦 ∣ 𝑦 = 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } → ( ⦋ 𝐴 / 𝑥 ⦌ { 𝐵 } = ⦋ 𝐴 / 𝑥 ⦌ { 𝑦 ∣ 𝑦 = 𝐵 } ↔ ⦋ 𝐴 / 𝑥 ⦌ { 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } ) ) |
28 |
27
|
biimpd |
⊢ ( ⦋ 𝐴 / 𝑥 ⦌ { 𝑦 ∣ 𝑦 = 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } → ( ⦋ 𝐴 / 𝑥 ⦌ { 𝐵 } = ⦋ 𝐴 / 𝑥 ⦌ { 𝑦 ∣ 𝑦 = 𝐵 } → ⦋ 𝐴 / 𝑥 ⦌ { 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } ) ) |
29 |
21 26 28
|
e11 |
⊢ ( 𝐴 ∈ 𝑉 ▶ ⦋ 𝐴 / 𝑥 ⦌ { 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } ) |
30 |
|
df-sn |
⊢ { ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } |
31 |
|
eqeq2 |
⊢ ( { ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } → ( ⦋ 𝐴 / 𝑥 ⦌ { 𝐵 } = { ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } ↔ ⦋ 𝐴 / 𝑥 ⦌ { 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } ) ) |
32 |
31
|
biimprcd |
⊢ ( ⦋ 𝐴 / 𝑥 ⦌ { 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } → ( { ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } = { 𝑦 ∣ 𝑦 = ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } → ⦋ 𝐴 / 𝑥 ⦌ { 𝐵 } = { ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } ) ) |
33 |
29 30 32
|
e10 |
⊢ ( 𝐴 ∈ 𝑉 ▶ ⦋ 𝐴 / 𝑥 ⦌ { 𝐵 } = { ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } ) |
34 |
33
|
in1 |
⊢ ( 𝐴 ∈ 𝑉 → ⦋ 𝐴 / 𝑥 ⦌ { 𝐵 } = { ⦋ 𝐴 / 𝑥 ⦌ 𝐵 } ) |