Description: The ratio of nonnegative and positive numbers is nonnegative. (Contributed by Mario Carneiro, 28-May-2016)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | rpgecld.1 | |- ( ph -> A e. RR ) |
|
| rpgecld.2 | |- ( ph -> B e. RR+ ) |
||
| divge0d.3 | |- ( ph -> 0 <_ A ) |
||
| Assertion | divge0d | |- ( ph -> 0 <_ ( A / B ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | rpgecld.1 | |- ( ph -> A e. RR ) |
|
| 2 | rpgecld.2 | |- ( ph -> B e. RR+ ) |
|
| 3 | divge0d.3 | |- ( ph -> 0 <_ A ) |
|
| 4 | 2 | rpregt0d | |- ( ph -> ( B e. RR /\ 0 < B ) ) |
| 5 | divge0 | |- ( ( ( A e. RR /\ 0 <_ A ) /\ ( B e. RR /\ 0 < B ) ) -> 0 <_ ( A / B ) ) |
|
| 6 | 1 3 4 5 | syl21anc | |- ( ph -> 0 <_ ( A / B ) ) |