Metamath Proof Explorer


Theorem iscmgmALT

Description: The predicate "is a commutative magma". (Contributed by AV, 20-Jan-2020) (New usage is discouraged.) (Proof modification is discouraged.)

Ref Expression
Hypotheses ismgmALT.b ⊢ 𝐵 = ( Base ‘ 𝑀 )
ismgmALT.o ⊢ ⚬ = ( +g ‘ 𝑀 )
Assertion iscmgmALT ( 𝑀 ∈ CMgmALT ↔ ( 𝑀 ∈ MgmALT ∧ ⚬ comLaw 𝐵 ) )

Proof

Step Hyp Ref Expression
1 ismgmALT.b ⊢ 𝐵 = ( Base ‘ 𝑀 )
2 ismgmALT.o ⊢ ⚬ = ( +g ‘ 𝑀 )
3 fveq2 ⊢ ( 𝑚 = 𝑀 → ( +g ‘ 𝑚 ) = ( +g ‘ 𝑀 ) )
4 fveq2 ⊢ ( 𝑚 = 𝑀 → ( Base ‘ 𝑚 ) = ( Base ‘ 𝑀 ) )
5 3 4 breq12d ⊢ ( 𝑚 = 𝑀 → ( ( +g ‘ 𝑚 ) comLaw ( Base ‘ 𝑚 ) ↔ ( +g ‘ 𝑀 ) comLaw ( Base ‘ 𝑀 ) ) )
6 2 1 breq12i ⊢ ( ⚬ comLaw 𝐵 ↔ ( +g ‘ 𝑀 ) comLaw ( Base ‘ 𝑀 ) )
7 5 6 bitr4di ⊢ ( 𝑚 = 𝑀 → ( ( +g ‘ 𝑚 ) comLaw ( Base ‘ 𝑚 ) ↔ ⚬ comLaw 𝐵 ) )
8 df-cmgm2 ⊢ CMgmALT = { 𝑚 ∈ MgmALT ∣ ( +g ‘ 𝑚 ) comLaw ( Base ‘ 𝑚 ) }
9 7 8 elrab2 ⊢ ( 𝑀 ∈ CMgmALT ↔ ( 𝑀 ∈ MgmALT ∧ ⚬ comLaw 𝐵 ) )