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| Mirrors > Home > MPE Home > Th. List > condan | Structured version Visualization version Unicode version | ||
| Description: Proof by contradiction. (Contributed by NM, 9-Feb-2006.) (Proof shortened by Wolf Lammen, 19-Jun-2014.) |
| Ref | Expression |
|---|---|
| condan.1 |
|
| condan.2 |
|
| Ref | Expression |
|---|---|
| condan |
|
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | condan.1 |
. . 3
| |
| 2 | condan.2 |
. . 3
| |
| 3 | 1, 2 | pm2.65da 600 |
. 2
|
| 4 | 3 | notnotrd 128 |
1
|
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