Description: Closure law for the extended division. (Contributed by Thierry Arnoux, 15-Mar-2017)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | xdivcl | ⊢ ( ( 𝐴 ∈ ℝ* ∧ 𝐵 ∈ ℝ ∧ 𝐵 ≠ 0 ) → ( 𝐴 /𝑒 𝐵 ) ∈ ℝ* ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | simp1 | ⊢ ( ( 𝐴 ∈ ℝ* ∧ 𝐵 ∈ ℝ ∧ 𝐵 ≠ 0 ) → 𝐴 ∈ ℝ* ) | |
| 2 | simp2 | ⊢ ( ( 𝐴 ∈ ℝ* ∧ 𝐵 ∈ ℝ ∧ 𝐵 ≠ 0 ) → 𝐵 ∈ ℝ ) | |
| 3 | simp3 | ⊢ ( ( 𝐴 ∈ ℝ* ∧ 𝐵 ∈ ℝ ∧ 𝐵 ≠ 0 ) → 𝐵 ≠ 0 ) | |
| 4 | 1 2 3 | xdivcld | ⊢ ( ( 𝐴 ∈ ℝ* ∧ 𝐵 ∈ ℝ ∧ 𝐵 ≠ 0 ) → ( 𝐴 /𝑒 𝐵 ) ∈ ℝ* ) |