Description: Expand a restricted existential quantifier to primitives while contracting a double negation. (Contributed by Rohan Ridenour, 13-Aug-2023)
Ref | Expression | ||
---|---|---|---|
Hypothesis | expandrexn.1 | ||
Assertion | expandrexn |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | expandrexn.1 | ||
2 | 1 | rexbii | |
3 | df-rex | ||
4 | exanali | ||
5 | 2 3 4 | 3bitri |