This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: The absolute value of the imaginary part of a non-real, complex number, is strictly positive. (Contributed by Glauco Siliprandi, 5-Feb-2022)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | absimnre.1 | ⊢ ( 𝜑 → 𝐴 ∈ ℂ ) | |
| absimnre.2 | ⊢ ( 𝜑 → ¬ 𝐴 ∈ ℝ ) | ||
| Assertion | absimnre | ⊢ ( 𝜑 → ( abs ‘ ( ℑ ‘ 𝐴 ) ) ∈ ℝ+ ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | absimnre.1 | ⊢ ( 𝜑 → 𝐴 ∈ ℂ ) | |
| 2 | absimnre.2 | ⊢ ( 𝜑 → ¬ 𝐴 ∈ ℝ ) | |
| 3 | 1 | imcld | ⊢ ( 𝜑 → ( ℑ ‘ 𝐴 ) ∈ ℝ ) |
| 4 | 3 | recnd | ⊢ ( 𝜑 → ( ℑ ‘ 𝐴 ) ∈ ℂ ) |
| 5 | reim0b | ⊢ ( 𝐴 ∈ ℂ → ( 𝐴 ∈ ℝ ↔ ( ℑ ‘ 𝐴 ) = 0 ) ) | |
| 6 | 1 5 | syl | ⊢ ( 𝜑 → ( 𝐴 ∈ ℝ ↔ ( ℑ ‘ 𝐴 ) = 0 ) ) |
| 7 | 2 6 | mtbid | ⊢ ( 𝜑 → ¬ ( ℑ ‘ 𝐴 ) = 0 ) |
| 8 | 7 | neqned | ⊢ ( 𝜑 → ( ℑ ‘ 𝐴 ) ≠ 0 ) |
| 9 | 4 8 | absrpcld | ⊢ ( 𝜑 → ( abs ‘ ( ℑ ‘ 𝐴 ) ) ∈ ℝ+ ) |