| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | eldifsn 4785 | . 2
⊢ (𝐴 ∈ (𝐾 ∖ { 0 }) ↔ (𝐴 ∈ 𝐾 ∧ 𝐴 ≠ 0 )) | 
| 2 |  | elfvdm 6942 | . . . . . . . 8
⊢ (𝐵 ∈ (LBasis‘𝑊) → 𝑊 ∈ dom LBasis) | 
| 3 |  | lbsss.j | . . . . . . . 8
⊢ 𝐽 = (LBasis‘𝑊) | 
| 4 | 2, 3 | eleq2s 2858 | . . . . . . 7
⊢ (𝐵 ∈ 𝐽 → 𝑊 ∈ dom LBasis) | 
| 5 |  | lbsss.v | . . . . . . . 8
⊢ 𝑉 = (Base‘𝑊) | 
| 6 |  | lbsind.f | . . . . . . . 8
⊢ 𝐹 = (Scalar‘𝑊) | 
| 7 |  | lbsind.s | . . . . . . . 8
⊢  · = (
·𝑠 ‘𝑊) | 
| 8 |  | lbsind.k | . . . . . . . 8
⊢ 𝐾 = (Base‘𝐹) | 
| 9 |  | lbssp.n | . . . . . . . 8
⊢ 𝑁 = (LSpan‘𝑊) | 
| 10 |  | lbsind.z | . . . . . . . 8
⊢  0 =
(0g‘𝐹) | 
| 11 | 5, 6, 7, 8, 3, 9, 10 | islbs 21076 | . . . . . . 7
⊢ (𝑊 ∈ dom LBasis → (𝐵 ∈ 𝐽 ↔ (𝐵 ⊆ 𝑉 ∧ (𝑁‘𝐵) = 𝑉 ∧ ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ (𝐾 ∖ { 0 }) ¬ (𝑦 · 𝑥) ∈ (𝑁‘(𝐵 ∖ {𝑥}))))) | 
| 12 | 4, 11 | syl 17 | . . . . . 6
⊢ (𝐵 ∈ 𝐽 → (𝐵 ∈ 𝐽 ↔ (𝐵 ⊆ 𝑉 ∧ (𝑁‘𝐵) = 𝑉 ∧ ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ (𝐾 ∖ { 0 }) ¬ (𝑦 · 𝑥) ∈ (𝑁‘(𝐵 ∖ {𝑥}))))) | 
| 13 | 12 | ibi 267 | . . . . 5
⊢ (𝐵 ∈ 𝐽 → (𝐵 ⊆ 𝑉 ∧ (𝑁‘𝐵) = 𝑉 ∧ ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ (𝐾 ∖ { 0 }) ¬ (𝑦 · 𝑥) ∈ (𝑁‘(𝐵 ∖ {𝑥})))) | 
| 14 | 13 | simp3d 1144 | . . . 4
⊢ (𝐵 ∈ 𝐽 → ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ (𝐾 ∖ { 0 }) ¬ (𝑦 · 𝑥) ∈ (𝑁‘(𝐵 ∖ {𝑥}))) | 
| 15 |  | oveq2 7440 | . . . . . . 7
⊢ (𝑥 = 𝐸 → (𝑦 · 𝑥) = (𝑦 · 𝐸)) | 
| 16 |  | sneq 4635 | . . . . . . . . 9
⊢ (𝑥 = 𝐸 → {𝑥} = {𝐸}) | 
| 17 | 16 | difeq2d 4125 | . . . . . . . 8
⊢ (𝑥 = 𝐸 → (𝐵 ∖ {𝑥}) = (𝐵 ∖ {𝐸})) | 
| 18 | 17 | fveq2d 6909 | . . . . . . 7
⊢ (𝑥 = 𝐸 → (𝑁‘(𝐵 ∖ {𝑥})) = (𝑁‘(𝐵 ∖ {𝐸}))) | 
| 19 | 15, 18 | eleq12d 2834 | . . . . . 6
⊢ (𝑥 = 𝐸 → ((𝑦 · 𝑥) ∈ (𝑁‘(𝐵 ∖ {𝑥})) ↔ (𝑦 · 𝐸) ∈ (𝑁‘(𝐵 ∖ {𝐸})))) | 
| 20 | 19 | notbid 318 | . . . . 5
⊢ (𝑥 = 𝐸 → (¬ (𝑦 · 𝑥) ∈ (𝑁‘(𝐵 ∖ {𝑥})) ↔ ¬ (𝑦 · 𝐸) ∈ (𝑁‘(𝐵 ∖ {𝐸})))) | 
| 21 |  | oveq1 7439 | . . . . . . 7
⊢ (𝑦 = 𝐴 → (𝑦 · 𝐸) = (𝐴 · 𝐸)) | 
| 22 | 21 | eleq1d 2825 | . . . . . 6
⊢ (𝑦 = 𝐴 → ((𝑦 · 𝐸) ∈ (𝑁‘(𝐵 ∖ {𝐸})) ↔ (𝐴 · 𝐸) ∈ (𝑁‘(𝐵 ∖ {𝐸})))) | 
| 23 | 22 | notbid 318 | . . . . 5
⊢ (𝑦 = 𝐴 → (¬ (𝑦 · 𝐸) ∈ (𝑁‘(𝐵 ∖ {𝐸})) ↔ ¬ (𝐴 · 𝐸) ∈ (𝑁‘(𝐵 ∖ {𝐸})))) | 
| 24 | 20, 23 | rspc2v 3632 | . . . 4
⊢ ((𝐸 ∈ 𝐵 ∧ 𝐴 ∈ (𝐾 ∖ { 0 })) → (∀𝑥 ∈ 𝐵 ∀𝑦 ∈ (𝐾 ∖ { 0 }) ¬ (𝑦 · 𝑥) ∈ (𝑁‘(𝐵 ∖ {𝑥})) → ¬ (𝐴 · 𝐸) ∈ (𝑁‘(𝐵 ∖ {𝐸})))) | 
| 25 | 14, 24 | syl5com 31 | . . 3
⊢ (𝐵 ∈ 𝐽 → ((𝐸 ∈ 𝐵 ∧ 𝐴 ∈ (𝐾 ∖ { 0 })) → ¬ (𝐴 · 𝐸) ∈ (𝑁‘(𝐵 ∖ {𝐸})))) | 
| 26 | 25 | impl 455 | . 2
⊢ (((𝐵 ∈ 𝐽 ∧ 𝐸 ∈ 𝐵) ∧ 𝐴 ∈ (𝐾 ∖ { 0 })) → ¬ (𝐴 · 𝐸) ∈ (𝑁‘(𝐵 ∖ {𝐸}))) | 
| 27 | 1, 26 | sylan2br 595 | 1
⊢ (((𝐵 ∈ 𝐽 ∧ 𝐸 ∈ 𝐵) ∧ (𝐴 ∈ 𝐾 ∧ 𝐴 ≠ 0 )) → ¬ (𝐴 · 𝐸) ∈ (𝑁‘(𝐵 ∖ {𝐸}))) |