Description: A topological division ring is a division ring. (Contributed by Mario Carneiro, 5-Oct-2015)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | tdrgdrng | ⊢ ( 𝑅 ∈ TopDRing → 𝑅 ∈ DivRing ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | eqid | ⊢ ( mulGrp ‘ 𝑅 ) = ( mulGrp ‘ 𝑅 ) | |
| 2 | eqid | ⊢ ( Unit ‘ 𝑅 ) = ( Unit ‘ 𝑅 ) | |
| 3 | 1 2 | istdrg | ⊢ ( 𝑅 ∈ TopDRing ↔ ( 𝑅 ∈ TopRing ∧ 𝑅 ∈ DivRing ∧ ( ( mulGrp ‘ 𝑅 ) ↾s ( Unit ‘ 𝑅 ) ) ∈ TopGrp ) ) |
| 4 | 3 | simp2bi | ⊢ ( 𝑅 ∈ TopDRing → 𝑅 ∈ DivRing ) |