Description: Contrapositive inference for inequality. (Contributed by NM, 9-Aug-2006) (Proof shortened by Wolf Lammen, 22-Nov-2019)
Ref | Expression | ||
---|---|---|---|
Hypothesis | necon3i.1 | |
|
Assertion | necon3i | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | necon3i.1 | |
|
2 | 1 | necon3ai | |
3 | 2 | neqned | |