Description: If the first input is true, then the adder sum is equivalent to the biconditionality of the other two inputs. (Contributed by Mario Carneiro, 4-Sep-2016) (Proof shortened by Wolf Lammen, 11-Jul-2020)
Ref | Expression | ||
---|---|---|---|
Assertion | had1 |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | hadrot | ||
2 | hadbi | ||
3 | 1 2 | bitri | |
4 | biass | ||
5 | 3 4 | mpbir | |
6 | 5 | biimpri |