Proof of Theorem fniunfv
| Step | Hyp | Ref
| Expression |
| 1 | | fndm 2723 |
. . . . . . . . . . 11
⊢ (F Fn
A → dom F = A) |
| 2 | 1 | eleq2d 1156 |
. . . . . . . . . 10
⊢ (F Fn
A → (x ∈ dom F
↔ x ∈ A)) |
| 3 | | visset 1350 |
. . . . . . . . . . 11
⊢ x
∈ V |
| 4 | 3 | opeldm 2534 |
. . . . . . . . . 10
⊢ (〈x, y〉
∈ F → x ∈ dom F) |
| 5 | 2, 4 | syl5bi 183 |
. . . . . . . . 9
⊢ (F Fn
A → (〈x, y〉
∈ F → x ∈ A)) |
| 6 | | pm4.71r 482 |
. . . . . . . . 9
⊢ ((〈x, y〉
∈ F → x ∈ A)
↔ (〈x, y〉 ∈ F
↔ (x ∈ A ∧ 〈x,
y〉 ∈ F))) |
| 7 | 5, 6 | sylib 173 |
. . . . . . . 8
⊢ (F Fn
A → (〈x, y〉
∈ F ↔ (x ∈ A ∧
〈x, y〉 ∈ F))) |
| 8 | | visset 1350 |
. . . . . . . . . . . 12
⊢ y
∈ V |
| 9 | 8 | fnfvop 2856 |
. . . . . . . . . . 11
⊢ ((F Fn
A ∧ x ∈ A)
→ ((F ‘x) = y ↔
〈x, y〉 ∈ F)) |
| 10 | | cleqcom 1103 |
. . . . . . . . . . 11
⊢ ((F
‘x) = y ↔ y =
(F ‘x)) |
| 11 | 9, 10 | syl5rbbr 413 |
. . . . . . . . . 10
⊢ ((F Fn
A ∧ x ∈ A)
→ (〈x, y〉 ∈ F
↔ y = (F ‘x))) |
| 12 | 11 | exp 291 |
. . . . . . . . 9
⊢ (F Fn
A → (x ∈ A
→ (〈x, y〉 ∈ F
↔ y = (F ‘x)))) |
| 13 | 12 | pm5.32d 491 |
. . . . . . . 8
⊢ (F Fn
A → ((x ∈ A ∧
〈x, y〉 ∈ F) ↔ (x
∈ A ∧ y = (F
‘x)))) |
| 14 | 7, 13 | bitrd 406 |
. . . . . . 7
⊢ (F Fn
A → (〈x, y〉
∈ F ↔ (x ∈ A ∧
y = (F
‘x)))) |
| 15 | 14 | biexdv 936 |
. . . . . 6
⊢ (F Fn
A → (∃x〈x,
y〉 ∈ F ↔ ∃x(x ∈
A ∧ y = (F
‘x)))) |
| 16 | | df-rex 1206 |
. . . . . 6
⊢ (∃x ∈ A
y = (F
‘x) ↔ ∃x(x ∈
A ∧ y = (F
‘x))) |
| 17 | 15, 16 | syl6bbr 416 |
. . . . 5
⊢ (F Fn
A → (∃x〈x,
y〉 ∈ F ↔ ∃x ∈ A
y = (F
‘x))) |
| 18 | 17 | biabdv 1183 |
. . . 4
⊢ (F Fn
A → {y∣∃x〈x,
y〉 ∈ F} = {y∣∃x
∈ A y = (F
‘x)}) |
| 19 | | dfrn3 2524 |
. . . 4
⊢ ran F
= {y∣∃x〈x,
y〉 ∈ F} |
| 20 | 18, 19 | syl5req 1137 |
. . 3
⊢ (F Fn
A → {y∣∃x
∈ A y = (F
‘x)} = ran F) |
| 21 | 20 | unieqd 1929 |
. 2
⊢ (F Fn
A → ∪{y∣∃x
∈ A y = (F
‘x)} = ∪ran F) |
| 22 | | fvex 2838 |
. . 3
⊢ (F
‘x) ∈ V |
| 23 | 22 | dfiun2 2014 |
. 2
⊢ ∪x ∈ A
(F ‘x) = ∪{y∣∃x
∈ A y = (F
‘x)} |
| 24 | 21, 23 | syl5eq 1136 |
1
⊢ (F Fn
A → ∪x ∈ A (F
‘x) = ∪ran
F) |