Metamath Proof Explorer


Theorem sn-redivcld

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

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

Proof

Step Hyp Ref Expression
1 redivvald.a ( 𝜑𝐴 ∈ ℝ )
2 redivvald.b ( 𝜑𝐵 ∈ ℝ )
3 redivvald.z ( 𝜑𝐵 ≠ 0 )
4 1 2 3 redivvald ( 𝜑 → ( 𝐴 / 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 / 𝐵 ) ∈ ℝ )