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Related theorems Unicode version |
| Description: Deduction negating both sides of a logical equivalence. |
| Ref | Expression |
|---|---|
| bid.1 |
|
| Ref | Expression |
|---|---|
| notbid |
|
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | bid.1 |
. 2
| |
| 2 | notbi 711 |
. 2
| |
| 3 | 1, 2 | sylib 242 |
1
|