This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: Closure of the addition operation of a non-unital ring. (Contributed by AV, 16-Feb-2025)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | rngacl.b | ⊢ 𝐵 = ( Base ‘ 𝑅 ) | |
| rngacl.p | ⊢ + = ( +g ‘ 𝑅 ) | ||
| Assertion | rngacl | ⊢ ( ( 𝑅 ∈ Rng ∧ 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ) → ( 𝑋 + 𝑌 ) ∈ 𝐵 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | rngacl.b | ⊢ 𝐵 = ( Base ‘ 𝑅 ) | |
| 2 | rngacl.p | ⊢ + = ( +g ‘ 𝑅 ) | |
| 3 | rnggrp | ⊢ ( 𝑅 ∈ Rng → 𝑅 ∈ Grp ) | |
| 4 | 1 2 | grpcl | ⊢ ( ( 𝑅 ∈ Grp ∧ 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ) → ( 𝑋 + 𝑌 ) ∈ 𝐵 ) |
| 5 | 3 4 | syl3an1 | ⊢ ( ( 𝑅 ∈ Rng ∧ 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ) → ( 𝑋 + 𝑌 ) ∈ 𝐵 ) |