Metamath Proof Explorer


Theorem nghmghm

Description: A normed group homomorphism is a group homomorphism. (Contributed by Mario Carneiro, 18-Oct-2015)

Ref Expression
Assertion nghmghm F S NGHom T F S GrpHom T

Proof

Step Hyp Ref Expression
1 eqid S normOp T = S normOp T
2 1 isnghm F S NGHom T S NrmGrp T NrmGrp F S GrpHom T S normOp T F
3 2 simprbi F S NGHom T F S GrpHom T S normOp T F
4 3 simpld F S NGHom T F S GrpHom T