Metamath Proof Explorer


Theorem noreceuw

Description: If a surreal has a reciprocal, then it has unique division. (Contributed by Scott Fenton, 12-Mar-2025)

Ref Expression
Assertion noreceuw
|- ( ( ( A e. No /\ A =/= 0s /\ B e. No ) /\ E. x e. No ( A x.s x ) = 1s ) -> E! y e. No ( A x.s y ) = B )

Proof

Step Hyp Ref Expression
1 norecdiv
 |-  ( ( ( A e. No /\ A =/= 0s /\ B e. No ) /\ E. x e. No ( A x.s x ) = 1s ) -> E. y e. No ( A x.s y ) = B )
2 divsmo
 |-  ( ( A e. No /\ A =/= 0s ) -> E* y e. No ( A x.s y ) = B )
3 2 3adant3
 |-  ( ( A e. No /\ A =/= 0s /\ B e. No ) -> E* y e. No ( A x.s y ) = B )
4 3 adantr
 |-  ( ( ( A e. No /\ A =/= 0s /\ B e. No ) /\ E. x e. No ( A x.s x ) = 1s ) -> E* y e. No ( A x.s y ) = B )
5 reu5
 |-  ( E! y e. No ( A x.s y ) = B <-> ( E. y e. No ( A x.s y ) = B /\ E* y e. No ( A x.s y ) = B ) )
6 1 4 5 sylanbrc
 |-  ( ( ( A e. No /\ A =/= 0s /\ B e. No ) /\ E. x e. No ( A x.s x ) = 1s ) -> E! y e. No ( A x.s y ) = B )