Description: Case where diffi is a biconditional. (Contributed by Thierry Arnoux, 27-Jun-2024)
Ref | Expression | ||
---|---|---|---|
Assertion | diffib |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | diffi | ||
2 | 1 | adantl | |
3 | difinf | ||
4 | 3 | ancoms | |
5 | 4 | ex | |
6 | 5 | con4d | |
7 | 6 | imp | |
8 | 2 7 | impbida |