Metamath Proof Explorer


Theorem smgrpismgmOLD

Description: Obsolete version of sgrpmgm as of 3-Feb-2020. A semigroup is a magma. (Contributed by FL, 2-Nov-2009) (New usage is discouraged.) (Proof modification is discouraged.)

Ref Expression
Assertion smgrpismgmOLD ( 𝐺 ∈ SemiGrp → 𝐺 ∈ Magma )

Proof

Step Hyp Ref Expression
1 elin ( 𝐺 ∈ ( Magma ∩ Ass ) ↔ ( 𝐺 ∈ Magma ∧ 𝐺 ∈ Ass ) )
2 1 simplbi ( 𝐺 ∈ ( Magma ∩ Ass ) → 𝐺 ∈ Magma )
3 df-sgrOLD SemiGrp = ( Magma ∩ Ass )
4 2 3 eleq2s ( 𝐺 ∈ SemiGrp → 𝐺 ∈ Magma )