Proof of Theorem mapdom2lem
| Step | Hyp | Ref
| Expression |
| 1 | | mapdom1.3 |
. . . . . . . 8
⊢ C
∈ V |
| 2 | | visset 1350 |
. . . . . . . 8
⊢ z
∈ V |
| 3 | 1, 2 | elmap 3265 |
. . . . . . 7
⊢ (x
∈ (C ↑m
z) ↔ x:z–→C) |
| 4 | 3 | biimp 133 |
. . . . . 6
⊢ (x
∈ (C ↑m
z) → x:z–→C) |
| 5 | | fdm 2756 |
. . . . . 6
⊢ (x:z–→C
→ dom x = z) |
| 6 | 4, 5 | syl 12 |
. . . . 5
⊢ (x
∈ (C ↑m
z) → dom x = z) |
| 7 | | visset 1350 |
. . . . . . . 8
⊢ w
∈ V |
| 8 | 7 | fconst 2774 |
. . . . . . 7
⊢ ((B
∖ z) × {w}):(B ∖
z)–→{w} |
| 9 | | fdm 2756 |
. . . . . . 7
⊢ (((B
∖ z) × {w}):(B ∖
z)–→{w} → dom ((B ∖ z)
× {w}) = (B ∖ z)) |
| 10 | 8, 9 | ax-mp 6 |
. . . . . 6
⊢ dom ((B ∖ z)
× {w}) = (B ∖ z) |
| 11 | 10 | a1i 7 |
. . . . 5
⊢ (x
∈ (C ↑m
z) → dom ((B ∖ z)
× {w}) = (B ∖ z)) |
| 12 | 6, 11 | ineq12d 1646 |
. . . 4
⊢ (x
∈ (C ↑m
z) → (dom x ∩ dom ((B
∖ z) × {w})) = (z ∩
(B ∖ z))) |
| 13 | | difdisj 1758 |
. . . 4
⊢ (z
∩ (B ∖ z)) = ∅ |
| 14 | 12, 13 | syl6eq 1140 |
. . 3
⊢ (x
∈ (C ↑m
z) → (dom x ∩ dom ((B
∖ z) × {w})) = ∅) |
| 15 | | dmin 2537 |
. . . . 5
⊢ dom (x
∩ ((B ∖ z) × {w}))
⊆ (dom x ∩ dom ((B ∖ z)
× {w})) |
| 16 | | sseq2 1522 |
. . . . 5
⊢ ((dom x ∩ dom ((B
∖ z) × {w})) = ∅ → (dom (x ∩ ((B
∖ z) × {w})) ⊆ (dom x ∩ dom ((B
∖ z) × {w})) ↔ dom (x ∩ ((B
∖ z) × {w})) ⊆ ∅)) |
| 17 | 15, 16 | mpbii 168 |
. . . 4
⊢ ((dom x ∩ dom ((B
∖ z) × {w})) = ∅ → dom (x ∩ ((B
∖ z) × {w})) ⊆ ∅) |
| 18 | | ss0 1727 |
. . . 4
⊢ (dom (x ∩ ((B
∖ z) × {w})) ⊆ ∅ → dom (x ∩ ((B
∖ z) × {w})) = ∅) |
| 19 | 17, 18 | syl 12 |
. . 3
⊢ ((dom x ∩ dom ((B
∖ z) × {w})) = ∅ → dom (x ∩ ((B
∖ z) × {w})) = ∅) |
| 20 | 14, 19 | syl 12 |
. 2
⊢ (x
∈ (C ↑m
z) → dom (x ∩ ((B
∖ z) × {w})) = ∅) |
| 21 | | relxp 2486 |
. . . . 5
⊢ Rel ((B ∖ z)
× {w}) |
| 22 | | relin 2491 |
. . . . 5
⊢ (Rel ((B ∖ z)
× {w}) → Rel (((B ∖ z)
× {w}) ∩ x)) |
| 23 | 21, 22 | ax-mp 6 |
. . . 4
⊢ Rel (((B ∖ z)
× {w}) ∩ x) |
| 24 | | incom 1636 |
. . . . 5
⊢ (((B
∖ z) × {w}) ∩ x) =
(x ∩ ((B ∖ z)
× {w})) |
| 25 | | releq 2477 |
. . . . 5
⊢ ((((B
∖ z) × {w}) ∩ x) =
(x ∩ ((B ∖ z)
× {w})) → (Rel (((B ∖ z)
× {w}) ∩ x) ↔ Rel (x
∩ ((B ∖ z) × {w})))) |
| 26 | 24, 25 | ax-mp 6 |
. . . 4
⊢ (Rel (((B ∖ z)
× {w}) ∩ x) ↔ Rel (x
∩ ((B ∖ z) × {w}))) |
| 27 | 23, 26 | mpbi 164 |
. . 3
⊢ Rel (x
∩ ((B ∖ z) × {w})) |
| 28 | | reldm0 2550 |
. . 3
⊢ (Rel (x ∩ ((B
∖ z) × {w})) → ((x
∩ ((B ∖ z) × {w}))
= ∅ ↔ dom (x ∩ ((B ∖ z)
× {w})) = ∅)) |
| 29 | 27, 28 | ax-mp 6 |
. 2
⊢ ((x
∩ ((B ∖ z) × {w}))
= ∅ ↔ dom (x ∩ ((B ∖ z)
× {w})) = ∅) |
| 30 | 20, 29 | sylibr 175 |
1
⊢ (x
∈ (C ↑m
z) → (x ∩ ((B
∖ z) × {w})) = ∅) |