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 ) |
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 ) |