| Step | Hyp | Ref
| Expression |
| 1 | | scaffval.a |
. 2
⊢ ∙ = (
·sf ‘𝑊) |
| 2 | | fveq2 6886 |
. . . . . . . 8
⊢ (𝑤 = 𝑊 → (Scalar‘𝑤) = (Scalar‘𝑊)) |
| 3 | | scaffval.f |
. . . . . . . 8
⊢ 𝐹 = (Scalar‘𝑊) |
| 4 | 2, 3 | eqtr4di 2787 |
. . . . . . 7
⊢ (𝑤 = 𝑊 → (Scalar‘𝑤) = 𝐹) |
| 5 | 4 | fveq2d 6890 |
. . . . . 6
⊢ (𝑤 = 𝑊 → (Base‘(Scalar‘𝑤)) = (Base‘𝐹)) |
| 6 | | scaffval.k |
. . . . . 6
⊢ 𝐾 = (Base‘𝐹) |
| 7 | 5, 6 | eqtr4di 2787 |
. . . . 5
⊢ (𝑤 = 𝑊 → (Base‘(Scalar‘𝑤)) = 𝐾) |
| 8 | | fveq2 6886 |
. . . . . 6
⊢ (𝑤 = 𝑊 → (Base‘𝑤) = (Base‘𝑊)) |
| 9 | | scaffval.b |
. . . . . 6
⊢ 𝐵 = (Base‘𝑊) |
| 10 | 8, 9 | eqtr4di 2787 |
. . . . 5
⊢ (𝑤 = 𝑊 → (Base‘𝑤) = 𝐵) |
| 11 | | fveq2 6886 |
. . . . . . 7
⊢ (𝑤 = 𝑊 → (
·𝑠 ‘𝑤) = ( ·𝑠
‘𝑊)) |
| 12 | | scaffval.s |
. . . . . . 7
⊢ · = (
·𝑠 ‘𝑊) |
| 13 | 11, 12 | eqtr4di 2787 |
. . . . . 6
⊢ (𝑤 = 𝑊 → (
·𝑠 ‘𝑤) = · ) |
| 14 | 13 | oveqd 7430 |
. . . . 5
⊢ (𝑤 = 𝑊 → (𝑥( ·𝑠
‘𝑤)𝑦) = (𝑥 · 𝑦)) |
| 15 | 7, 10, 14 | mpoeq123dv 7490 |
. . . 4
⊢ (𝑤 = 𝑊 → (𝑥 ∈ (Base‘(Scalar‘𝑤)), 𝑦 ∈ (Base‘𝑤) ↦ (𝑥( ·𝑠
‘𝑤)𝑦)) = (𝑥 ∈ 𝐾, 𝑦 ∈ 𝐵 ↦ (𝑥 · 𝑦))) |
| 16 | | df-scaf 20829 |
. . . 4
⊢
·sf = (𝑤 ∈ V ↦ (𝑥 ∈ (Base‘(Scalar‘𝑤)), 𝑦 ∈ (Base‘𝑤) ↦ (𝑥( ·𝑠
‘𝑤)𝑦))) |
| 17 | 6 | fvexi 6900 |
. . . . 5
⊢ 𝐾 ∈ V |
| 18 | 9 | fvexi 6900 |
. . . . 5
⊢ 𝐵 ∈ V |
| 19 | 12 | fvexi 6900 |
. . . . . . 7
⊢ · ∈
V |
| 20 | 19 | rnex 7914 |
. . . . . 6
⊢ ran · ∈
V |
| 21 | | p0ex 5364 |
. . . . . 6
⊢ {∅}
∈ V |
| 22 | 20, 21 | unex 7746 |
. . . . 5
⊢ (ran
·
∪ {∅}) ∈ V |
| 23 | | df-ov 7416 |
. . . . . . 7
⊢ (𝑥 · 𝑦) = ( · ‘〈𝑥, 𝑦〉) |
| 24 | | fvrn0 6916 |
. . . . . . 7
⊢ ( ·
‘〈𝑥, 𝑦〉) ∈ (ran · ∪
{∅}) |
| 25 | 23, 24 | eqeltri 2829 |
. . . . . 6
⊢ (𝑥 · 𝑦) ∈ (ran · ∪
{∅}) |
| 26 | 25 | rgen2w 3055 |
. . . . 5
⊢
∀𝑥 ∈
𝐾 ∀𝑦 ∈ 𝐵 (𝑥 · 𝑦) ∈ (ran · ∪
{∅}) |
| 27 | 17, 18, 22, 26 | mpoexw 8085 |
. . . 4
⊢ (𝑥 ∈ 𝐾, 𝑦 ∈ 𝐵 ↦ (𝑥 · 𝑦)) ∈ V |
| 28 | 15, 16, 27 | fvmpt 6996 |
. . 3
⊢ (𝑊 ∈ V → (
·sf ‘𝑊) = (𝑥 ∈ 𝐾, 𝑦 ∈ 𝐵 ↦ (𝑥 · 𝑦))) |
| 29 | | fvprc 6878 |
. . . 4
⊢ (¬
𝑊 ∈ V → (
·sf ‘𝑊) = ∅) |
| 30 | | fvprc 6878 |
. . . . . . 7
⊢ (¬
𝑊 ∈ V →
(Base‘𝑊) =
∅) |
| 31 | 9, 30 | eqtrid 2781 |
. . . . . 6
⊢ (¬
𝑊 ∈ V → 𝐵 = ∅) |
| 32 | 31 | olcd 874 |
. . . . 5
⊢ (¬
𝑊 ∈ V → (𝐾 = ∅ ∨ 𝐵 = ∅)) |
| 33 | | 0mpo0 7498 |
. . . . 5
⊢ ((𝐾 = ∅ ∨ 𝐵 = ∅) → (𝑥 ∈ 𝐾, 𝑦 ∈ 𝐵 ↦ (𝑥 · 𝑦)) = ∅) |
| 34 | 32, 33 | syl 17 |
. . . 4
⊢ (¬
𝑊 ∈ V → (𝑥 ∈ 𝐾, 𝑦 ∈ 𝐵 ↦ (𝑥 · 𝑦)) = ∅) |
| 35 | 29, 34 | eqtr4d 2772 |
. . 3
⊢ (¬
𝑊 ∈ V → (
·sf ‘𝑊) = (𝑥 ∈ 𝐾, 𝑦 ∈ 𝐵 ↦ (𝑥 · 𝑦))) |
| 36 | 28, 35 | pm2.61i 182 |
. 2
⊢ (
·sf ‘𝑊) = (𝑥 ∈ 𝐾, 𝑦 ∈ 𝐵 ↦ (𝑥 · 𝑦)) |
| 37 | 1, 36 | eqtri 2757 |
1
⊢ ∙ =
(𝑥 ∈ 𝐾, 𝑦 ∈ 𝐵 ↦ (𝑥 · 𝑦)) |