Description: Relationship between three restricted universal and existential quantifiers. (Contributed by Thierry Arnoux, 12-Jul-2020)
Ref | Expression | ||
---|---|---|---|
Assertion | rexnal3 | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | rexnal | |
|
2 | 1 | 2rexbii | |
3 | rexnal2 | |
|
4 | 2 3 | bitri | |