Metamath Proof Explorer


Theorem divmulswd

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

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

Proof

Step Hyp Ref Expression
1 divmulswd.1
 |-  ( ph -> A e. No )
2 divmulswd.2
 |-  ( ph -> B e. No )
3 divmulswd.3
 |-  ( ph -> C e. No )
4 divmulswd.4
 |-  ( ph -> C =/= 0s )
5 divmulswd.5
 |-  ( ph -> E. x e. No ( C x.s x ) = 1s )
6 3 4 jca
 |-  ( ph -> ( C e. No /\ C =/= 0s ) )
7 divmulsw
 |-  ( ( ( 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 ) )