Metamath Proof Explorer


Theorem cnnrg

Description: The complex numbers form a normed ring. (Contributed by Mario Carneiro, 4-Oct-2015)

Ref Expression
Assertion cnnrg ℂfld ∈ NrmRing

Proof

Step Hyp Ref Expression
1 cnngp ⊢ ℂfld ∈ NrmGrp
2 absabv ⊢ abs ∈ ( AbsVal ‘ ℂfld )
3 cnfldnm ⊢ abs = ( norm ‘ ℂfld )
4 eqid ⊢ ( AbsVal ‘ ℂfld ) = ( AbsVal ‘ ℂfld )
5 3 4 isnrg ⊢ ( ℂfld ∈ NrmRing ↔ ( ℂfld ∈ NrmGrp ∧ abs ∈ ( AbsVal ‘ ℂfld ) ) )
6 1 2 5 mpbir2an ⊢ ℂfld ∈ NrmRing