Description: 3imp with innermost implication of the hypothesis a biconditional. (Contributed by Alan Sare, 6-Nov-2017)
Ref | Expression | ||
---|---|---|---|
Hypothesis | bi33imp12.1 | |
|
Assertion | bi33imp12 | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | bi33imp12.1 | |
|
2 | biimp | |
|
3 | 1 2 | syl6 | |
4 | 3 | 3imp | |