Metamath Proof Explorer


Theorem sltmuld

Description: An ordering relationship for surreal multiplication. Compare theorem 8(iii) of Conway p. 19. (Contributed by Scott Fenton, 6-Mar-2025)

Ref Expression
Hypotheses sltmuld.1 φ A No
sltmuld.2 φ B No
sltmuld.3 φ C No
sltmuld.4 φ D No
sltmuld.5 φ A < s B
sltmuld.6 φ C < s D
Assertion sltmuld Could not format assertion : No typesetting found for |- ( ph -> ( ( A x.s D ) -s ( A x.s C ) )

Proof

Step Hyp Ref Expression
1 sltmuld.1 φ A No
2 sltmuld.2 φ B No
3 sltmuld.3 φ C No
4 sltmuld.4 φ D No
5 sltmuld.5 φ A < s B
6 sltmuld.6 φ C < s D
7 sltmul Could not format ( ( ( A e. No /\ B e. No ) /\ ( C e. No /\ D e. No ) ) -> ( ( A ( ( A x.s D ) -s ( A x.s C ) ) ( ( A ( ( A x.s D ) -s ( A x.s C ) )
8 1 2 3 4 7 syl22anc Could not format ( ph -> ( ( A ( ( A x.s D ) -s ( A x.s C ) ) ( ( A ( ( A x.s D ) -s ( A x.s C ) )
9 5 6 8 mp2and Could not format ( ph -> ( ( A x.s D ) -s ( A x.s C ) ) ( ( A x.s D ) -s ( A x.s C ) )