Metamath Proof Explorer


Theorem submgmbas

Description: The base set of a submagma. (Contributed by AV, 26-Feb-2020)

Ref Expression
Hypothesis submgmmgm.h ⊢ H = M ↾ 𝑠 S
Assertion submgmbas ⊢ S ∈ SubMgm ⁡ M → S = Base H

Proof

Step Hyp Ref Expression
1 submgmmgm.h ⊢ H = M ↾ 𝑠 S
2 eqid ⊢ Base M = Base M
3 2 submgmss ⊢ S ∈ SubMgm ⁡ M → S ⊆ Base M
4 1 2 ressbas2 ⊢ S ⊆ Base M → S = Base H
5 3 4 syl ⊢ S ∈ SubMgm ⁡ M → S = Base H