Proof of Theorem funimaexg
| Step | Hyp | Ref
| Expression |
| 1 | | imaeq2 3398 |
. . . . 5
⊢ (w =
B → (A “ w) =
(A “ B)) |
| 2 | 1 | eleq1d 1538 |
. . . 4
⊢ (w =
B → ((A “ w)
∈ V ↔ (A “ B) ∈ V)) |
| 3 | 2 | imbi2d 611 |
. . 3
⊢ (w =
B → ((Fun A → (A
“ w) ∈ V) ↔ (Fun
A → (A “ B)
∈ V))) |
| 4 | | dffun5 3525 |
. . . . 5
⊢ (Fun A
↔ (Rel A ⋀ ∀x∃z∀y(〈x,
y〉 ∈ A → y =
z))) |
| 5 | 4 | pm3.27bi 326 |
. . . 4
⊢ (Fun A
→ ∀x∃z∀y(〈x,
y〉 ∈ A → y =
z)) |
| 6 | | ax-17 970 |
. . . . . 6
⊢ (〈x, y〉
∈ A → ∀z〈x,
y〉 ∈ A) |
| 7 | 6 | axrep4 2693 |
. . . . 5
⊢ (∀x∃z∀y(〈x,
y〉 ∈ A → y =
z) → ∃z∀y(y ∈
z ↔ ∃x(x ∈
w ⋀ 〈x, y〉
∈ A))) |
| 8 | | isset 1811 |
. . . . . 6
⊢ ((A
“ w) ∈ V ↔
∃z z = (A “
w)) |
| 9 | | dfima3 3402 |
. . . . . . . . 9
⊢ (A
“ w) = {y∣∃x(x ∈
w ⋀ 〈x, y〉
∈ A)} |
| 10 | 9 | eqeq2i 1483 |
. . . . . . . 8
⊢ (z =
(A “ w) ↔ z =
{y∣∃x(x ∈
w ⋀ 〈x, y〉
∈ A)}) |
| 11 | | abeq2 1566 |
. . . . . . . 8
⊢ (z =
{y∣∃x(x ∈
w ⋀ 〈x, y〉
∈ A)} ↔ ∀y(y ∈
z ↔ ∃x(x ∈
w ⋀ 〈x, y〉
∈ A))) |
| 12 | 10, 11 | bitr 173 |
. . . . . . 7
⊢ (z =
(A “ w) ↔ ∀y(y ∈
z ↔ ∃x(x ∈
w ⋀ 〈x, y〉
∈ A))) |
| 13 | 12 | exbii 1050 |
. . . . . 6
⊢ (∃z z = (A “ w)
↔ ∃z∀y(y ∈
z ↔ ∃x(x ∈
w ⋀ 〈x, y〉
∈ A))) |
| 14 | 8, 13 | bitr 173 |
. . . . 5
⊢ ((A
“ w) ∈ V ↔
∃z∀y(y ∈
z ↔ ∃x(x ∈
w ⋀ 〈x, y〉
∈ A))) |
| 15 | 7, 14 | sylibr 200 |
. . . 4
⊢ (∀x∃z∀y(〈x,
y〉 ∈ A → y =
z) → (A “ w)
∈ V) |
| 16 | 5, 15 | syl 10 |
. . 3
⊢ (Fun A
→ (A “ w) ∈ V) |
| 17 | 3, 16 | vtoclg 1844 |
. 2
⊢ (B
∈ C → (Fun A → (A
“ B) ∈ V)) |
| 18 | 17 | impcom 351 |
1
⊢ ((Fun A ⋀ B
∈ C) → (A “ B)
∈ V) |