Metamath Proof Explorer


Theorem ringridmd

Description: The unity element of a ring is a right multiplicative identity. (Contributed by SN, 14-Aug-2024)

Ref Expression
Hypotheses ringlidmd.b ⊢ B = Base R
ringlidmd.t ⊢ · ˙ = ⋅ R
ringlidmd.u ⊢ 1 ˙ = 1 R
ringlidmd.r ⊢ φ → R ∈ Ring
ringlidmd.x ⊢ φ → X ∈ B
Assertion ringridmd ⊢ φ → X · ˙ 1 ˙ = X

Proof

Step Hyp Ref Expression
1 ringlidmd.b ⊢ B = Base R
2 ringlidmd.t ⊢ · ˙ = ⋅ R
3 ringlidmd.u ⊢ 1 ˙ = 1 R
4 ringlidmd.r ⊢ φ → R ∈ Ring
5 ringlidmd.x ⊢ φ → X ∈ B
6 1 2 3 ringridm ⊢ R ∈ Ring ∧ X ∈ B → X · ˙ 1 ˙ = X
7 4 5 6 syl2anc ⊢ φ → X · ˙ 1 ˙ = X