Metamath Proof Explorer


Theorem mgmhmf

Description: A magma homomorphism is a function. (Contributed by AV, 25-Feb-2020)

Ref Expression
Hypotheses mgmhmf.b 𝐵 = ( Base ‘ 𝑆 )
mgmhmf.c 𝐶 = ( Base ‘ 𝑇 )
Assertion mgmhmf ( 𝐹 ∈ ( 𝑆 MgmHom 𝑇 ) → 𝐹 : 𝐵𝐶 )

Proof

Step Hyp Ref Expression
1 mgmhmf.b 𝐵 = ( Base ‘ 𝑆 )
2 mgmhmf.c 𝐶 = ( Base ‘ 𝑇 )
3 eqid ( +g𝑆 ) = ( +g𝑆 )
4 eqid ( +g𝑇 ) = ( +g𝑇 )
5 1 2 3 4 ismgmhm ( 𝐹 ∈ ( 𝑆 MgmHom 𝑇 ) ↔ ( ( 𝑆 ∈ Mgm ∧ 𝑇 ∈ Mgm ) ∧ ( 𝐹 : 𝐵𝐶 ∧ ∀ 𝑥𝐵𝑦𝐵 ( 𝐹 ‘ ( 𝑥 ( +g𝑆 ) 𝑦 ) ) = ( ( 𝐹𝑥 ) ( +g𝑇 ) ( 𝐹𝑦 ) ) ) ) )
6 simprl ( ( ( 𝑆 ∈ Mgm ∧ 𝑇 ∈ Mgm ) ∧ ( 𝐹 : 𝐵𝐶 ∧ ∀ 𝑥𝐵𝑦𝐵 ( 𝐹 ‘ ( 𝑥 ( +g𝑆 ) 𝑦 ) ) = ( ( 𝐹𝑥 ) ( +g𝑇 ) ( 𝐹𝑦 ) ) ) ) → 𝐹 : 𝐵𝐶 )
7 5 6 sylbi ( 𝐹 ∈ ( 𝑆 MgmHom 𝑇 ) → 𝐹 : 𝐵𝐶 )