Description: Membership in the set of positive reals. (Contributed by NM, 27-Oct-2007)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | elrp | |- ( A e. RR+ <-> ( A e. RR /\ 0 < A ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | breq2 | |- ( x = A -> ( 0 < x <-> 0 < A ) ) |
|
| 2 | df-rp | |- RR+ = { x e. RR | 0 < x } |
|
| 3 | 1 2 | elrab2 | |- ( A e. RR+ <-> ( A e. RR /\ 0 < A ) ) |