Metamath Proof Explorer


Theorem imcli

Description: The imaginary part of a complex number is real (closure law). (Contributed by NM, 11-May-1999)

Ref Expression
Hypothesis recl.1 ⊢ A ∈ ℂ
Assertion imcli ⊢ ℑ ⁡ A ∈ ℝ

Proof

Step Hyp Ref Expression
1 recl.1 ⊢ A ∈ ℂ
2 imcl ⊢ A ∈ ℂ → ℑ ⁡ A ∈ ℝ
3 1 2 ax-mp ⊢ ℑ ⁡ A ∈ ℝ