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 ) |