Description: A star ring is a ring. (Contributed by Mario Carneiro, 6-Oct-2015)
Ref | Expression | ||
---|---|---|---|
Assertion | srngring | ⊢ ( 𝑅 ∈ *-Ring → 𝑅 ∈ Ring ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | eqid | ⊢ ( oppr ‘ 𝑅 ) = ( oppr ‘ 𝑅 ) | |
2 | eqid | ⊢ ( *rf ‘ 𝑅 ) = ( *rf ‘ 𝑅 ) | |
3 | 1 2 | srngrhm | ⊢ ( 𝑅 ∈ *-Ring → ( *rf ‘ 𝑅 ) ∈ ( 𝑅 RingHom ( oppr ‘ 𝑅 ) ) ) |
4 | rhmrcl1 | ⊢ ( ( *rf ‘ 𝑅 ) ∈ ( 𝑅 RingHom ( oppr ‘ 𝑅 ) ) → 𝑅 ∈ Ring ) | |
5 | 3 4 | syl | ⊢ ( 𝑅 ∈ *-Ring → 𝑅 ∈ Ring ) |