Description: The exponential of a complex number is nonzero. Corollary 15-4.3 of Gleason p. 309. (Contributed by NM, 13-Jan-2006) (Revised by Mario Carneiro, 29-Apr-2014) (Proof shortened by TA, 14-Nov-2025)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | efne0 | ⊢ ( 𝐴 ∈ ℂ → ( exp ‘ 𝐴 ) ≠ 0 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | id | ⊢ ( 𝐴 ∈ ℂ → 𝐴 ∈ ℂ ) | |
| 2 | 1 | efne0d | ⊢ ( 𝐴 ∈ ℂ → ( exp ‘ 𝐴 ) ≠ 0 ) |