Description: Existential uniqueness of real negatives. (Contributed by Steven Nguyen, 7-Jan-2023)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | renegeu | ⊢ ( 𝐴 ∈ ℝ → ∃! 𝑥 ∈ ℝ ( 𝐴 + 𝑥 ) = 0 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | id | ⊢ ( 𝐴 ∈ ℝ → 𝐴 ∈ ℝ ) | |
| 2 | ax-rnegex | ⊢ ( 𝐴 ∈ ℝ → ∃ 𝑥 ∈ ℝ ( 𝐴 + 𝑥 ) = 0 ) | |
| 3 | 1 2 | renegeulem | ⊢ ( 𝐴 ∈ ℝ → ∃! 𝑥 ∈ ℝ ( 𝐴 + 𝑥 ) = 0 ) |