Proof of Theorem oaword
| Step | Hyp | Ref
| Expression |
| 1 | | oaord 3149 |
. . 3
⊢ ((A
∈ On ∧ B ∈ On ∧ C ∈ On) → (A ∈ B
↔ (C +o A) ∈ (C
+o B))) |
| 2 | | oacan 3150 |
. . . . 5
⊢ ((C
∈ On ∧ A ∈ On ∧ B ∈ On) → ((C +o A) = (C
+o B) ↔ A = B)) |
| 3 | 2 | 3coml 617 |
. . . 4
⊢ ((A
∈ On ∧ B ∈ On ∧ C ∈ On) → ((C +o A) = (C
+o B) ↔ A = B)) |
| 4 | 3 | bicomd 399 |
. . 3
⊢ ((A
∈ On ∧ B ∈ On ∧ C ∈ On) → (A = B ↔
(C +o A) = (C
+o B))) |
| 5 | 1, 4 | orbi12d 475 |
. 2
⊢ ((A
∈ On ∧ B ∈ On ∧ C ∈ On) → ((A ∈ B ∨
A = B)
↔ ((C +o A) ∈ (C
+o B) ∨ (C +o A) = (C
+o B)))) |
| 6 | | onsseleq 2254 |
. . 3
⊢ ((A
∈ On ∧ B ∈ On) →
(A ⊆ B ↔ (A
∈ B ∨ A = B))) |
| 7 | 6 | 3adant3 599 |
. 2
⊢ ((A
∈ On ∧ B ∈ On ∧ C ∈ On) → (A ⊆ B
↔ (A ∈ B ∨ A =
B))) |
| 8 | | oacl 3138 |
. . . . . . 7
⊢ ((C
∈ On ∧ A ∈ On) →
(C +o A) ∈ On) |
| 9 | | oacl 3138 |
. . . . . . 7
⊢ ((C
∈ On ∧ B ∈ On) →
(C +o B) ∈ On) |
| 10 | 8, 9 | anim12i 268 |
. . . . . 6
⊢ (((C
∈ On ∧ A ∈ On) ∧
(C ∈ On ∧ B ∈ On)) → ((C +o A) ∈ On ∧ (C +o B) ∈ On)) |
| 11 | 10 | anandis 394 |
. . . . 5
⊢ ((C
∈ On ∧ (A ∈ On ∧ B ∈ On)) → ((C +o A) ∈ On ∧ (C +o B) ∈ On)) |
| 12 | 11 | ancoms 334 |
. . . 4
⊢ (((A
∈ On ∧ B ∈ On) ∧ C ∈ On) → ((C +o A) ∈ On ∧ (C +o B) ∈ On)) |
| 13 | 12 | 3impa 609 |
. . 3
⊢ ((A
∈ On ∧ B ∈ On ∧ C ∈ On) → ((C +o A) ∈ On ∧ (C +o B) ∈ On)) |
| 14 | | onsseleq 2254 |
. . 3
⊢ (((C
+o A) ∈ On ∧
(C +o B) ∈ On) → ((C +o A) ⊆ (C
+o B) ↔ ((C +o A) ∈ (C
+o B) ∨ (C +o A) = (C
+o B)))) |
| 15 | 13, 14 | syl 12 |
. 2
⊢ ((A
∈ On ∧ B ∈ On ∧ C ∈ On) → ((C +o A) ⊆ (C
+o B) ↔ ((C +o A) ∈ (C
+o B) ∨ (C +o A) = (C
+o B)))) |
| 16 | 5, 7, 15 | 3bitr4d 424 |
1
⊢ ((A
∈ On ∧ B ∈ On ∧ C ∈ On) → (A ⊆ B
↔ (C +o A) ⊆ (C
+o B))) |