Metamath Proof Explorer
Description: An abelian group operation is commutative, deduction version.
(Contributed by Thierry Arnoux, 15-Feb-2026)
|
|
Ref |
Expression |
|
Hypotheses |
ablcomd.1 |
⊢ 𝐵 = ( Base ‘ 𝐺 ) |
|
|
ablcomd.2 |
⊢ + = ( +g ‘ 𝐺 ) |
|
|
ablcomd.3 |
⊢ ( 𝜑 → 𝐺 ∈ Abel ) |
|
|
ablcomd.4 |
⊢ ( 𝜑 → 𝑋 ∈ 𝐵 ) |
|
|
ablcomd.5 |
⊢ ( 𝜑 → 𝑌 ∈ 𝐵 ) |
|
Assertion |
ablcomd |
⊢ ( 𝜑 → ( 𝑋 + 𝑌 ) = ( 𝑌 + 𝑋 ) ) |
Proof
| Step |
Hyp |
Ref |
Expression |
| 1 |
|
ablcomd.1 |
⊢ 𝐵 = ( Base ‘ 𝐺 ) |
| 2 |
|
ablcomd.2 |
⊢ + = ( +g ‘ 𝐺 ) |
| 3 |
|
ablcomd.3 |
⊢ ( 𝜑 → 𝐺 ∈ Abel ) |
| 4 |
|
ablcomd.4 |
⊢ ( 𝜑 → 𝑋 ∈ 𝐵 ) |
| 5 |
|
ablcomd.5 |
⊢ ( 𝜑 → 𝑌 ∈ 𝐵 ) |
| 6 |
1 2
|
ablcom |
⊢ ( ( 𝐺 ∈ Abel ∧ 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ) → ( 𝑋 + 𝑌 ) = ( 𝑌 + 𝑋 ) ) |
| 7 |
3 4 5 6
|
syl3anc |
⊢ ( 𝜑 → ( 𝑋 + 𝑌 ) = ( 𝑌 + 𝑋 ) ) |