Description: Surreal multiplication by zero. (Contributed by Scott Fenton, 4-Feb-2025)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | muls02 | |- ( A e. No -> ( 0s x.s A ) = 0s ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | 0sno | |- 0s e. No | |
| 2 | mulscom | |- ( ( 0s e. No /\ A e. No ) -> ( 0s x.s A ) = ( A x.s 0s ) ) | |
| 3 | 1 2 | mpan | |- ( A e. No -> ( 0s x.s A ) = ( A x.s 0s ) ) | 
| 4 | muls01 | |- ( A e. No -> ( A x.s 0s ) = 0s ) | |
| 5 | 3 4 | eqtrd | |- ( A e. No -> ( 0s x.s A ) = 0s ) |