Description: A Hausdorff space is locally Hausdorff. (Contributed by Mario Carneiro, 2-Mar-2015)
Ref | Expression | ||
---|---|---|---|
Assertion | hauslly | ⊢ ( 𝐽 ∈ Haus → 𝐽 ∈ Locally Haus ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | resthaus | ⊢ ( ( 𝑗 ∈ Haus ∧ 𝑥 ∈ 𝑗 ) → ( 𝑗 ↾t 𝑥 ) ∈ Haus ) | |
2 | 1 | adantl | ⊢ ( ( ⊤ ∧ ( 𝑗 ∈ Haus ∧ 𝑥 ∈ 𝑗 ) ) → ( 𝑗 ↾t 𝑥 ) ∈ Haus ) |
3 | haustop | ⊢ ( 𝑗 ∈ Haus → 𝑗 ∈ Top ) | |
4 | 3 | ssriv | ⊢ Haus ⊆ Top |
5 | 4 | a1i | ⊢ ( ⊤ → Haus ⊆ Top ) |
6 | 2 5 | restlly | ⊢ ( ⊤ → Haus ⊆ Locally Haus ) |
7 | 6 | mptru | ⊢ Haus ⊆ Locally Haus |
8 | 7 | sseli | ⊢ ( 𝐽 ∈ Haus → 𝐽 ∈ Locally Haus ) |