Metamath Proof Explorer


Theorem redivvald

Description: Value of real division, which is the (unique) real x such that ( B x. x ) = A . (Contributed by SN, 25-Nov-2025)

Ref Expression
Hypotheses redivvald.a φ A
redivvald.b φ B
redivvald.z φ B 0
Assertion redivvald Could not format assertion : No typesetting found for |- ( ph -> ( A /R B ) = ( iota_ x e. RR ( B x. x ) = A ) ) with typecode |-

Proof

Step Hyp Ref Expression
1 redivvald.a φ A
2 redivvald.b φ B
3 redivvald.z φ B 0
4 2 3 eldifsnd φ B 0
5 eqeq2 z = A y x = z y x = A
6 5 riotabidv z = A ι x | y x = z = ι x | y x = A
7 oveq1 y = B y x = B x
8 7 eqeq1d y = B y x = A B x = A
9 8 riotabidv y = B ι x | y x = A = ι x | B x = A
10 df-rediv Could not format /R = ( z e. RR , y e. ( RR \ { 0 } ) |-> ( iota_ x e. RR ( y x. x ) = z ) ) : No typesetting found for |- /R = ( z e. RR , y e. ( RR \ { 0 } ) |-> ( iota_ x e. RR ( y x. x ) = z ) ) with typecode |-
11 riotaex ι x | B x = A V
12 6 9 10 11 ovmpo Could not format ( ( A e. RR /\ B e. ( RR \ { 0 } ) ) -> ( A /R B ) = ( iota_ x e. RR ( B x. x ) = A ) ) : No typesetting found for |- ( ( A e. RR /\ B e. ( RR \ { 0 } ) ) -> ( A /R B ) = ( iota_ x e. RR ( B x. x ) = A ) ) with typecode |-
13 1 4 12 syl2anc Could not format ( ph -> ( A /R B ) = ( iota_ x e. RR ( B x. x ) = A ) ) : No typesetting found for |- ( ph -> ( A /R B ) = ( iota_ x e. RR ( B x. x ) = A ) ) with typecode |-