| Step |
Hyp |
Ref |
Expression |
| 1 |
|
preq12bg |
⊢ ( ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐶 ∈ V ∧ 𝐷 ∈ V ) ) → ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } ↔ ( ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ∨ ( 𝐴 = 𝐷 ∧ 𝐵 = 𝐶 ) ) ) ) |
| 2 |
1
|
adantlr |
⊢ ( ( ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) ∧ ( 𝐶 ∈ V ∧ 𝐷 ∈ V ) ) → ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } ↔ ( ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ∨ ( 𝐴 = 𝐷 ∧ 𝐵 = 𝐶 ) ) ) ) |
| 3 |
|
idd |
⊢ ( 𝐴 ≠ 𝐷 → ( ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) → ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |
| 4 |
|
df-ne |
⊢ ( 𝐴 ≠ 𝐷 ↔ ¬ 𝐴 = 𝐷 ) |
| 5 |
|
pm2.21 |
⊢ ( ¬ 𝐴 = 𝐷 → ( 𝐴 = 𝐷 → ( 𝐵 = 𝐶 → ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) ) |
| 6 |
4 5
|
sylbi |
⊢ ( 𝐴 ≠ 𝐷 → ( 𝐴 = 𝐷 → ( 𝐵 = 𝐶 → ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) ) |
| 7 |
6
|
impd |
⊢ ( 𝐴 ≠ 𝐷 → ( ( 𝐴 = 𝐷 ∧ 𝐵 = 𝐶 ) → ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |
| 8 |
3 7
|
jaod |
⊢ ( 𝐴 ≠ 𝐷 → ( ( ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ∨ ( 𝐴 = 𝐷 ∧ 𝐵 = 𝐶 ) ) → ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |
| 9 |
|
orc |
⊢ ( ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) → ( ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ∨ ( 𝐴 = 𝐷 ∧ 𝐵 = 𝐶 ) ) ) |
| 10 |
8 9
|
impbid1 |
⊢ ( 𝐴 ≠ 𝐷 → ( ( ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ∨ ( 𝐴 = 𝐷 ∧ 𝐵 = 𝐶 ) ) ↔ ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |
| 11 |
10
|
adantl |
⊢ ( ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) → ( ( ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ∨ ( 𝐴 = 𝐷 ∧ 𝐵 = 𝐶 ) ) ↔ ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |
| 12 |
11
|
ad2antlr |
⊢ ( ( ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) ∧ ( 𝐶 ∈ V ∧ 𝐷 ∈ V ) ) → ( ( ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ∨ ( 𝐴 = 𝐷 ∧ 𝐵 = 𝐶 ) ) ↔ ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |
| 13 |
2 12
|
bitrd |
⊢ ( ( ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) ∧ ( 𝐶 ∈ V ∧ 𝐷 ∈ V ) ) → ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } ↔ ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |
| 14 |
13
|
expcom |
⊢ ( ( 𝐶 ∈ V ∧ 𝐷 ∈ V ) → ( ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) → ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } ↔ ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) ) |
| 15 |
|
ianor |
⊢ ( ¬ ( 𝐶 ∈ V ∧ 𝐷 ∈ V ) ↔ ( ¬ 𝐶 ∈ V ∨ ¬ 𝐷 ∈ V ) ) |
| 16 |
|
simpl |
⊢ ( ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) → 𝐴 ≠ 𝐵 ) |
| 17 |
16
|
anim2i |
⊢ ( ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) → ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ 𝐴 ≠ 𝐵 ) ) |
| 18 |
|
df-3an |
⊢ ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ∧ 𝐴 ≠ 𝐵 ) ↔ ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ 𝐴 ≠ 𝐵 ) ) |
| 19 |
17 18
|
sylibr |
⊢ ( ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) → ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ∧ 𝐴 ≠ 𝐵 ) ) |
| 20 |
|
prneprprc |
⊢ ( ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ∧ 𝐴 ≠ 𝐵 ) ∧ ¬ 𝐶 ∈ V ) → { 𝐴 , 𝐵 } ≠ { 𝐶 , 𝐷 } ) |
| 21 |
19 20
|
sylan |
⊢ ( ( ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) ∧ ¬ 𝐶 ∈ V ) → { 𝐴 , 𝐵 } ≠ { 𝐶 , 𝐷 } ) |
| 22 |
21
|
ancoms |
⊢ ( ( ¬ 𝐶 ∈ V ∧ ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) ) → { 𝐴 , 𝐵 } ≠ { 𝐶 , 𝐷 } ) |
| 23 |
|
eqneqall |
⊢ ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } → ( { 𝐴 , 𝐵 } ≠ { 𝐶 , 𝐷 } → ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |
| 24 |
22 23
|
syl5com |
⊢ ( ( ¬ 𝐶 ∈ V ∧ ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) ) → ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } → ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |
| 25 |
|
prneprprc |
⊢ ( ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ∧ 𝐴 ≠ 𝐵 ) ∧ ¬ 𝐷 ∈ V ) → { 𝐴 , 𝐵 } ≠ { 𝐷 , 𝐶 } ) |
| 26 |
19 25
|
sylan |
⊢ ( ( ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) ∧ ¬ 𝐷 ∈ V ) → { 𝐴 , 𝐵 } ≠ { 𝐷 , 𝐶 } ) |
| 27 |
26
|
ancoms |
⊢ ( ( ¬ 𝐷 ∈ V ∧ ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) ) → { 𝐴 , 𝐵 } ≠ { 𝐷 , 𝐶 } ) |
| 28 |
|
prcom |
⊢ { 𝐶 , 𝐷 } = { 𝐷 , 𝐶 } |
| 29 |
28
|
eqeq2i |
⊢ ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } ↔ { 𝐴 , 𝐵 } = { 𝐷 , 𝐶 } ) |
| 30 |
|
eqneqall |
⊢ ( { 𝐴 , 𝐵 } = { 𝐷 , 𝐶 } → ( { 𝐴 , 𝐵 } ≠ { 𝐷 , 𝐶 } → ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |
| 31 |
29 30
|
sylbi |
⊢ ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } → ( { 𝐴 , 𝐵 } ≠ { 𝐷 , 𝐶 } → ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |
| 32 |
27 31
|
syl5com |
⊢ ( ( ¬ 𝐷 ∈ V ∧ ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) ) → ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } → ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |
| 33 |
24 32
|
jaoian |
⊢ ( ( ( ¬ 𝐶 ∈ V ∨ ¬ 𝐷 ∈ V ) ∧ ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) ) → ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } → ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |
| 34 |
|
preq12 |
⊢ ( ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) → { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } ) |
| 35 |
33 34
|
impbid1 |
⊢ ( ( ( ¬ 𝐶 ∈ V ∨ ¬ 𝐷 ∈ V ) ∧ ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) ) → ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } ↔ ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |
| 36 |
35
|
ex |
⊢ ( ( ¬ 𝐶 ∈ V ∨ ¬ 𝐷 ∈ V ) → ( ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) → ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } ↔ ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) ) |
| 37 |
15 36
|
sylbi |
⊢ ( ¬ ( 𝐶 ∈ V ∧ 𝐷 ∈ V ) → ( ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) → ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } ↔ ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) ) |
| 38 |
14 37
|
pm2.61i |
⊢ ( ( ( 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ) ∧ ( 𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐷 ) ) → ( { 𝐴 , 𝐵 } = { 𝐶 , 𝐷 } ↔ ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |