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 |