Metamath Proof Explorer


Theorem renegeu

Description: Existential uniqueness of real negatives. (Contributed by Steven Nguyen, 7-Jan-2023)

Ref Expression
Assertion renegeu ( 𝐴 ∈ ℝ → ∃! 𝑥 ∈ ℝ ( 𝐴 + 𝑥 ) = 0 )

Proof

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 )