Metamath Proof Explorer


Theorem sn-redivcld

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

Ref Expression
Hypotheses redivvald.a
|- ( ph -> A e. RR )
redivvald.b
|- ( ph -> B e. RR )
redivvald.z
|- ( ph -> B =/= 0 )
Assertion sn-redivcld
|- ( ph -> ( A /R B ) e. RR )

Proof

Step Hyp Ref Expression
1 redivvald.a
 |-  ( ph -> A e. RR )
2 redivvald.b
 |-  ( ph -> B e. RR )
3 redivvald.z
 |-  ( ph -> B =/= 0 )
4 1 2 3 redivvald
 |-  ( ph -> ( A /R B ) = ( iota_ x e. RR ( B x. x ) = A ) )
5 1 2 3 rediveud
 |-  ( ph -> E! x e. RR ( B x. x ) = A )
6 riotacl
 |-  ( E! x e. RR ( B x. x ) = A -> ( iota_ x e. RR ( B x. x ) = A ) e. RR )
7 5 6 syl
 |-  ( ph -> ( iota_ x e. RR ( B x. x ) = A ) e. RR )
8 4 7 eqeltrd
 |-  ( ph -> ( A /R B ) e. RR )