Description: Identity law for multiplication. (Contributed by Mario Carneiro, 27-May-2016)
Ref | Expression | ||
---|---|---|---|
Hypothesis | addcld.1 | ⊢ ( 𝜑 → 𝐴 ∈ ℂ ) | |
Assertion | mulid1d | ⊢ ( 𝜑 → ( 𝐴 · 1 ) = 𝐴 ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | addcld.1 | ⊢ ( 𝜑 → 𝐴 ∈ ℂ ) | |
2 | mulid1 | ⊢ ( 𝐴 ∈ ℂ → ( 𝐴 · 1 ) = 𝐴 ) | |
3 | 1 2 | syl | ⊢ ( 𝜑 → ( 𝐴 · 1 ) = 𝐴 ) |