Description: A positive real is a set of positive fractions. (Contributed by NM, 13-Mar-1996) (Revised by Mario Carneiro, 11-May-2013) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | elprnq | |- ( ( A e. P. /\ B e. A ) -> B e. Q. ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | prpssnq | |- ( A e. P. -> A C. Q. ) |
|
| 2 | 1 | pssssd | |- ( A e. P. -> A C_ Q. ) |
| 3 | 2 | sselda | |- ( ( A e. P. /\ B e. A ) -> B e. Q. ) |