Description: The empty structure has no subspaces (for use with fvco4i ). (Contributed by Stefan O'Rear, 31-Mar-2015)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | 00lss | ⊢ ∅ = ( LSubSp ‘ ∅ ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | noel | ⊢ ¬ 𝑎 ∈ ∅ | |
| 2 | base0 | ⊢ ∅ = ( Base ‘ ∅ ) | |
| 3 | eqid | ⊢ ( LSubSp ‘ ∅ ) = ( LSubSp ‘ ∅ ) | |
| 4 | 2 3 | lssss | ⊢ ( 𝑎 ∈ ( LSubSp ‘ ∅ ) → 𝑎 ⊆ ∅ ) |
| 5 | ss0 | ⊢ ( 𝑎 ⊆ ∅ → 𝑎 = ∅ ) | |
| 6 | 4 5 | syl | ⊢ ( 𝑎 ∈ ( LSubSp ‘ ∅ ) → 𝑎 = ∅ ) |
| 7 | 3 | lssn0 | ⊢ ( 𝑎 ∈ ( LSubSp ‘ ∅ ) → 𝑎 ≠ ∅ ) |
| 8 | 7 | neneqd | ⊢ ( 𝑎 ∈ ( LSubSp ‘ ∅ ) → ¬ 𝑎 = ∅ ) |
| 9 | 6 8 | pm2.65i | ⊢ ¬ 𝑎 ∈ ( LSubSp ‘ ∅ ) |
| 10 | 1 9 | 2false | ⊢ ( 𝑎 ∈ ∅ ↔ 𝑎 ∈ ( LSubSp ‘ ∅ ) ) |
| 11 | 10 | eqriv | ⊢ ∅ = ( LSubSp ‘ ∅ ) |