Description: Division of both sides of 'less than' by a positive number. (Contributed by NM, 16-May-1999)
Ref | Expression | ||
---|---|---|---|
Hypotheses | ltplus1.1 | |- A e. RR |
|
prodgt0.2 | |- B e. RR |
||
ltmul1.3 | |- C e. RR |
||
ltmul1i.4 | |- 0 < C |
||
Assertion | ltdiv1ii | |- ( A < B <-> ( A / C ) < ( B / C ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | ltplus1.1 | |- A e. RR |
|
2 | prodgt0.2 | |- B e. RR |
|
3 | ltmul1.3 | |- C e. RR |
|
4 | ltmul1i.4 | |- 0 < C |
|
5 | 1 2 3 | ltdiv1i | |- ( 0 < C -> ( A < B <-> ( A / C ) < ( B / C ) ) ) |
6 | 4 5 | ax-mp | |- ( A < B <-> ( A / C ) < ( B / C ) ) |