Proof of Theorem mdbr4
| Step | Hyp | Ref
| Expression |
| 1 | | mdbr2 5728 |
. 2
⊢ ((A
∈ Cℋ ∧ B
∈ Cℋ ) → (A Mℋ B ↔ ∀y ∈ Cℋ (y ⊆ B
→ ((y ∨ℋ A) ∩ B)
⊆ (y ∨ℋ (A ∩ B))))) |
| 2 | | chinclt 5416 |
. . . . . . . . . . 11
⊢ ((x
∈ Cℋ ∧ B
∈ Cℋ ) → (x ∩ B)
∈ Cℋ ) |
| 3 | 2 | ancoms 334 |
. . . . . . . . . 10
⊢ ((B
∈ Cℋ ∧ x
∈ Cℋ ) → (x ∩ B)
∈ Cℋ ) |
| 4 | | inss2 1658 |
. . . . . . . . . 10
⊢ (x
∩ B) ⊆ B |
| 5 | 3, 4 | jctir 241 |
. . . . . . . . 9
⊢ ((B
∈ Cℋ ∧ x
∈ Cℋ ) → ((x ∩ B)
∈ Cℋ ∧ (x
∩ B) ⊆ B)) |
| 6 | 5 | exp 291 |
. . . . . . . 8
⊢ (B
∈ Cℋ → (x
∈ Cℋ → ((x ∩ B)
∈ Cℋ ∧ (x
∩ B) ⊆ B))) |
| 7 | 6 | syl4d 28 |
. . . . . . 7
⊢ (B
∈ Cℋ → ((((x ∩ B)
∈ Cℋ ∧ (x
∩ B) ⊆ B) → (((x
∩ B) ∨ℋ A) ∩ B)
⊆ ((x ∩ B) ∨ℋ (A ∩ B)))
→ (x ∈ Cℋ
→ (((x ∩ B) ∨ℋ A) ∩ B)
⊆ ((x ∩ B) ∨ℋ (A ∩ B))))) |
| 8 | | impexp 276 |
. . . . . . 7
⊢ ((((x
∩ B) ∈ Cℋ
∧ (x ∩ B) ⊆ B)
→ (((x ∩ B) ∨ℋ A) ∩ B)
⊆ ((x ∩ B) ∨ℋ (A ∩ B)))
↔ ((x ∩ B) ∈ Cℋ →
((x ∩ B) ⊆ B
→ (((x ∩ B) ∨ℋ A) ∩ B)
⊆ ((x ∩ B) ∨ℋ (A ∩ B))))) |
| 9 | 7, 8 | syl5ibr 182 |
. . . . . 6
⊢ (B
∈ Cℋ → (((x ∩ B)
∈ Cℋ → ((x ∩ B)
⊆ B → (((x ∩ B)
∨ℋ A) ∩ B) ⊆ ((x
∩ B) ∨ℋ (A ∩ B))))
→ (x ∈ Cℋ
→ (((x ∩ B) ∨ℋ A) ∩ B)
⊆ ((x ∩ B) ∨ℋ (A ∩ B))))) |
| 10 | | sseq1 1521 |
. . . . . . . 8
⊢ (y =
(x ∩ B) → (y
⊆ B ↔ (x ∩ B)
⊆ B)) |
| 11 | | opreq1 3006 |
. . . . . . . . . 10
⊢ (y =
(x ∩ B) → (y
∨ℋ A) = ((x ∩ B)
∨ℋ A)) |
| 12 | 11 | ineq1d 1644 |
. . . . . . . . 9
⊢ (y =
(x ∩ B) → ((y
∨ℋ A) ∩ B) = (((x ∩
B) ∨ℋ A) ∩ B)) |
| 13 | | opreq1 3006 |
. . . . . . . . 9
⊢ (y =
(x ∩ B) → (y
∨ℋ (A ∩ B)) = ((x ∩
B) ∨ℋ (A ∩ B))) |
| 14 | 12, 13 | sseq12d 1529 |
. . . . . . . 8
⊢ (y =
(x ∩ B) → (((y
∨ℋ A) ∩ B) ⊆ (y
∨ℋ (A ∩ B)) ↔ (((x
∩ B) ∨ℋ A) ∩ B)
⊆ ((x ∩ B) ∨ℋ (A ∩ B)))) |
| 15 | 10, 14 | imbi12d 474 |
. . . . . . 7
⊢ (y =
(x ∩ B) → ((y
⊆ B → ((y ∨ℋ A) ∩ B)
⊆ (y ∨ℋ (A ∩ B)))
↔ ((x ∩ B) ⊆ B
→ (((x ∩ B) ∨ℋ A) ∩ B)
⊆ ((x ∩ B) ∨ℋ (A ∩ B))))) |
| 16 | 15 | rcla4v 1402 |
. . . . . 6
⊢ (∀y ∈ Cℋ (y ⊆ B
→ ((y ∨ℋ A) ∩ B)
⊆ (y ∨ℋ (A ∩ B)))
→ ((x ∩ B) ∈ Cℋ →
((x ∩ B) ⊆ B
→ (((x ∩ B) ∨ℋ A) ∩ B)
⊆ ((x ∩ B) ∨ℋ (A ∩ B))))) |
| 17 | 9, 16 | syl5 22 |
. . . . 5
⊢ (B
∈ Cℋ → (∀y ∈ Cℋ (y ⊆ B
→ ((y ∨ℋ A) ∩ B)
⊆ (y ∨ℋ (A ∩ B)))
→ (x ∈ Cℋ
→ (((x ∩ B) ∨ℋ A) ∩ B)
⊆ ((x ∩ B) ∨ℋ (A ∩ B))))) |
| 18 | 17 | r19.21adv 1262 |
. . . 4
⊢ (B
∈ Cℋ → (∀y ∈ Cℋ (y ⊆ B
→ ((y ∨ℋ A) ∩ B)
⊆ (y ∨ℋ (A ∩ B)))
→ ∀x ∈
Cℋ (((x ∩
B) ∨ℋ A) ∩ B)
⊆ ((x ∩ B) ∨ℋ (A ∩ B)))) |
| 19 | | dfss 1493 |
. . . . . . . . . . . 12
⊢ (x
⊆ B ↔ x = (x ∩
B)) |
| 20 | 19 | biimp 133 |
. . . . . . . . . . 11
⊢ (x
⊆ B → x = (x ∩
B)) |
| 21 | 20 | opreq1d 3012 |
. . . . . . . . . 10
⊢ (x
⊆ B → (x ∨ℋ A) = ((x ∩
B) ∨ℋ A)) |
| 22 | 21 | ineq1d 1644 |
. . . . . . . . 9
⊢ (x
⊆ B → ((x ∨ℋ A) ∩ B) =
(((x ∩ B) ∨ℋ A) ∩ B)) |
| 23 | 20 | opreq1d 3012 |
. . . . . . . . 9
⊢ (x
⊆ B → (x ∨ℋ (A ∩ B)) =
((x ∩ B) ∨ℋ (A ∩ B))) |
| 24 | 22, 23 | sseq12d 1529 |
. . . . . . . 8
⊢ (x
⊆ B → (((x ∨ℋ A) ∩ B)
⊆ (x ∨ℋ (A ∩ B))
↔ (((x ∩ B) ∨ℋ A) ∩ B)
⊆ ((x ∩ B) ∨ℋ (A ∩ B)))) |
| 25 | 24 | biimprcd 138 |
. . . . . . 7
⊢ ((((x
∩ B) ∨ℋ A) ∩ B)
⊆ ((x ∩ B) ∨ℋ (A ∩ B))
→ (x ⊆ B → ((x
∨ℋ A) ∩ B) ⊆ (x
∨ℋ (A ∩ B)))) |
| 26 | 25 | r19.20si 1254 |
. . . . . 6
⊢ (∀x ∈ Cℋ (((x ∩ B)
∨ℋ A) ∩ B) ⊆ ((x
∩ B) ∨ℋ (A ∩ B))
→ ∀x ∈
Cℋ (x ⊆
B → ((x ∨ℋ A) ∩ B)
⊆ (x ∨ℋ (A ∩ B)))) |
| 27 | | sseq1 1521 |
. . . . . . . 8
⊢ (x =
y → (x ⊆ B
↔ y ⊆ B)) |
| 28 | | opreq1 3006 |
. . . . . . . . . 10
⊢ (x =
y → (x ∨ℋ A) = (y
∨ℋ A)) |
| 29 | 28 | ineq1d 1644 |
. . . . . . . . 9
⊢ (x =
y → ((x ∨ℋ A) ∩ B) =
((y ∨ℋ A) ∩ B)) |
| 30 | | opreq1 3006 |
. . . . . . . . 9
⊢ (x =
y → (x ∨ℋ (A ∩ B)) =
(y ∨ℋ (A ∩ B))) |
| 31 | 29, 30 | sseq12d 1529 |
. . . . . . . 8
⊢ (x =
y → (((x ∨ℋ A) ∩ B)
⊆ (x ∨ℋ (A ∩ B))
↔ ((y ∨ℋ A) ∩ B)
⊆ (y ∨ℋ (A ∩ B)))) |
| 32 | 27, 31 | imbi12d 474 |
. . . . . . 7
⊢ (x =
y → ((x ⊆ B
→ ((x ∨ℋ A) ∩ B)
⊆ (x ∨ℋ (A ∩ B)))
↔ (y ⊆ B → ((y
∨ℋ A) ∩ B) ⊆ (y
∨ℋ (A ∩ B))))) |
| 33 | 32 | cbvralv 1333 |
. . . . . 6
⊢ (∀x ∈ Cℋ (x ⊆ B
→ ((x ∨ℋ A) ∩ B)
⊆ (x ∨ℋ (A ∩ B)))
↔ ∀y ∈
Cℋ (y ⊆
B → ((y ∨ℋ A) ∩ B)
⊆ (y ∨ℋ (A ∩ B)))) |
| 34 | 26, 33 | sylib 173 |
. . . . 5
⊢ (∀x ∈ Cℋ (((x ∩ B)
∨ℋ A) ∩ B) ⊆ ((x
∩ B) ∨ℋ (A ∩ B))
→ ∀y ∈
Cℋ (y ⊆
B → ((y ∨ℋ A) ∩ B)
⊆ (y ∨ℋ (A ∩ B)))) |
| 35 | 34 | a1i 7 |
. . . 4
⊢ (B
∈ Cℋ → (∀x ∈ Cℋ (((x ∩ B)
∨ℋ A) ∩ B) ⊆ ((x
∩ B) ∨ℋ (A ∩ B))
→ ∀y ∈
Cℋ (y ⊆
B → ((y ∨ℋ A) ∩ B)
⊆ (y ∨ℋ (A ∩ B))))) |
| 36 | 18, 35 | impbid 397 |
. . 3
⊢ (B
∈ Cℋ → (∀y ∈ Cℋ (y ⊆ B
→ ((y ∨ℋ A) ∩ B)
⊆ (y ∨ℋ (A ∩ B)))
↔ ∀x ∈
Cℋ (((x ∩
B) ∨ℋ A) ∩ B)
⊆ ((x ∩ B) ∨ℋ (A ∩ B)))) |
| 37 | 36 | adantl 305 |
. 2
⊢ ((A
∈ Cℋ ∧ B
∈ Cℋ ) → (∀y ∈ Cℋ (y ⊆ B
→ ((y ∨ℋ A) ∩ B)
⊆ (y ∨ℋ (A ∩ B)))
↔ ∀x ∈
Cℋ (((x ∩
B) ∨ℋ A) ∩ B)
⊆ ((x ∩ B) ∨ℋ (A ∩ B)))) |
| 38 | 1, 37 | bitrd 406 |
1
⊢ ((A
∈ Cℋ ∧ B
∈ Cℋ ) → (A Mℋ B ↔ ∀x ∈ Cℋ (((x ∩ B)
∨ℋ A) ∩ B) ⊆ ((x
∩ B) ∨ℋ (A ∩ B)))) |