Metamath Proof Explorer


Theorem mulid1d

Description: Identity law for multiplication. (Contributed by Mario Carneiro, 27-May-2016)

Ref Expression
Hypothesis addcld.1 ( 𝜑𝐴 ∈ ℂ )
Assertion mulid1d ( 𝜑 → ( 𝐴 · 1 ) = 𝐴 )

Proof

Step Hyp Ref Expression
1 addcld.1 ( 𝜑𝐴 ∈ ℂ )
2 mulid1 ( 𝐴 ∈ ℂ → ( 𝐴 · 1 ) = 𝐴 )
3 1 2 syl ( 𝜑 → ( 𝐴 · 1 ) = 𝐴 )