Description: Move conjunction outside of biconditional. (Contributed by Mario Carneiro, 11-Sep-2015) (Proof shortened by Wolf Lammen, 19-Jan-2020)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | baib.1 | ||
| Assertion | rbaibr |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | baib.1 | ||
| 2 | 1 | biancomi | |
| 3 | 2 | baibr |