Description: For all positive real numbers there is a smaller positive real number. (Contributed by AV, 5-Sep-2020)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | rpltrp | |- A. x e. RR+ E. y e. RR+ y < x |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | breq1 | |- ( y = ( x / 2 ) -> ( y < x <-> ( x / 2 ) < x ) ) |
|
| 2 | rphalfcl | |- ( x e. RR+ -> ( x / 2 ) e. RR+ ) |
|
| 3 | rphalflt | |- ( x e. RR+ -> ( x / 2 ) < x ) |
|
| 4 | 1 2 3 | rspcedvdw | |- ( x e. RR+ -> E. y e. RR+ y < x ) |
| 5 | 4 | rgen | |- A. x e. RR+ E. y e. RR+ y < x |