Description: Define the surreal less-than or equal predicate. Compare df-le . (Contributed by Scott Fenton, 8-Dec-2021)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | df-sle | |- <_s = ( ( No X. No ) \ `' |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 0 | csle | |- <_s |
|
| 1 | csur | |- No |
|
| 2 | 1 1 | cxp | |- ( No X. No ) |
| 3 | cslt | |- |
|
| 4 | 3 | ccnv | |- `' |
| 5 | 2 4 | cdif | |- ( ( No X. No ) \ `' |
| 6 | 0 5 | wceq | |- <_s = ( ( No X. No ) \ `' |