Description: 'Less than or equal to' is reflexive for extended reals. (Contributed by NM, 7-Feb-2007)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | xrleid | |- ( A e. RR* -> A <_ A ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | eqid | |- A = A |
|
| 2 | 1 | olci | |- ( A < A \/ A = A ) |
| 3 | xrleloe | |- ( ( A e. RR* /\ A e. RR* ) -> ( A <_ A <-> ( A < A \/ A = A ) ) ) |
|
| 4 | 2 3 | mpbiri | |- ( ( A e. RR* /\ A e. RR* ) -> A <_ A ) |
| 5 | 4 | anidms | |- ( A e. RR* -> A <_ A ) |