Metamath Proof Explorer


Theorem elre0re

Description: Specialized version of 0red without using ax-1cn and ax-cnre . (Contributed by Steven Nguyen, 28-Jan-2023)

Ref Expression
Assertion elre0re ( 𝐴 ∈ ℝ → 0 ∈ ℝ )

Proof

Step Hyp Ref Expression
1 ax-rnegex ( 𝐴 ∈ ℝ → ∃ 𝑥 ∈ ℝ ( 𝐴 + 𝑥 ) = 0 )
2 readdcl ( ( 𝐴 ∈ ℝ ∧ 𝑥 ∈ ℝ ) → ( 𝐴 + 𝑥 ) ∈ ℝ )
3 eleq1 ( ( 𝐴 + 𝑥 ) = 0 → ( ( 𝐴 + 𝑥 ) ∈ ℝ ↔ 0 ∈ ℝ ) )
4 2 3 syl5ibcom ( ( 𝐴 ∈ ℝ ∧ 𝑥 ∈ ℝ ) → ( ( 𝐴 + 𝑥 ) = 0 → 0 ∈ ℝ ) )
5 4 rexlimdva ( 𝐴 ∈ ℝ → ( ∃ 𝑥 ∈ ℝ ( 𝐴 + 𝑥 ) = 0 → 0 ∈ ℝ ) )
6 1 5 mpd ( 𝐴 ∈ ℝ → 0 ∈ ℝ )