Description: Division of a positive number by a positive number. (Contributed by Mario Carneiro, 28-May-2016)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | rpgecld.1 | |- ( ph -> A e. RR ) |
|
| rpgecld.2 | |- ( ph -> B e. RR+ ) |
||
| Assertion | gt0divd | |- ( ph -> ( 0 < A <-> 0 < ( A / B ) ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | rpgecld.1 | |- ( ph -> A e. RR ) |
|
| 2 | rpgecld.2 | |- ( ph -> B e. RR+ ) |
|
| 3 | 2 | rpred | |- ( ph -> B e. RR ) |
| 4 | 2 | rpgt0d | |- ( ph -> 0 < B ) |
| 5 | gt0div | |- ( ( A e. RR /\ B e. RR /\ 0 < B ) -> ( 0 < A <-> 0 < ( A / B ) ) ) |
|
| 6 | 1 3 4 5 | syl3anc | |- ( ph -> ( 0 < A <-> 0 < ( A / B ) ) ) |