Metamath Proof Explorer


Theorem divsmulwd

Description: Relationship between surreal division and multiplication. Weak version that does not assume reciprocals. (Contributed by Scott Fenton, 12-Mar-2025)

Ref Expression
Hypotheses divsmulwd.1
|- ( ph -> A e. No )
divsmulwd.2
|- ( ph -> B e. No )
divsmulwd.3
|- ( ph -> C e. No )
divsmulwd.4
|- ( ph -> C =/= 0s )
divsmulwd.5
|- ( ph -> E. x e. No ( C x.s x ) = 1s )
Assertion divsmulwd
|- ( ph -> ( ( A /su C ) = B <-> ( C x.s B ) = A ) )

Proof

Step Hyp Ref Expression
1 divsmulwd.1
 |-  ( ph -> A e. No )
2 divsmulwd.2
 |-  ( ph -> B e. No )
3 divsmulwd.3
 |-  ( ph -> C e. No )
4 divsmulwd.4
 |-  ( ph -> C =/= 0s )
5 divsmulwd.5
 |-  ( ph -> E. x e. No ( C x.s x ) = 1s )
6 3 4 jca
 |-  ( ph -> ( C e. No /\ C =/= 0s ) )
7 divsmulw
 |-  ( ( ( A e. No /\ B e. No /\ ( C e. No /\ C =/= 0s ) ) /\ E. x e. No ( C x.s x ) = 1s ) -> ( ( A /su C ) = B <-> ( C x.s B ) = A ) )
8 1 2 6 5 7 syl31anc
 |-  ( ph -> ( ( A /su C ) = B <-> ( C x.s B ) = A ) )