Metamath Proof Explorer


Theorem sn-redivcld

Description: Closure law for real division. (Contributed by SN, 25-Nov-2025)

Ref Expression
Hypotheses redivvald.a ⊢ ( 𝜑 → 𝐴 ∈ ℝ )
redivvald.b ⊢ ( 𝜑 → 𝐵 ∈ ℝ )
redivvald.z ⊢ ( 𝜑 → 𝐵 ≠ 0 )
Assertion sn-redivcld ( 𝜑 → ( 𝐴 /ℝ 𝐵 ) ∈ ℝ )

Proof

Step Hyp Ref Expression
1 redivvald.a ⊢ ( 𝜑 → 𝐴 ∈ ℝ )
2 redivvald.b ⊢ ( 𝜑 → 𝐵 ∈ ℝ )
3 redivvald.z ⊢ ( 𝜑 → 𝐵 ≠ 0 )
4 1 2 3 redivvald ⊢ ( 𝜑 → ( 𝐴 /ℝ 𝐵 ) = ( ℩ 𝑥 ∈ ℝ ( 𝐵 · 𝑥 ) = 𝐴 ) )
5 1 2 3 rediveud ⊢ ( 𝜑 → ∃! 𝑥 ∈ ℝ ( 𝐵 · 𝑥 ) = 𝐴 )
6 riotacl ⊢ ( ∃! 𝑥 ∈ ℝ ( 𝐵 · 𝑥 ) = 𝐴 → ( ℩ 𝑥 ∈ ℝ ( 𝐵 · 𝑥 ) = 𝐴 ) ∈ ℝ )
7 5 6 syl ⊢ ( 𝜑 → ( ℩ 𝑥 ∈ ℝ ( 𝐵 · 𝑥 ) = 𝐴 ) ∈ ℝ )
8 4 7 eqeltrd ⊢ ( 𝜑 → ( 𝐴 /ℝ 𝐵 ) ∈ ℝ )