Description: Express that an intersection is not empty. (Contributed by RP, 16-Apr-2020)
Ref | Expression | ||
---|---|---|---|
Assertion | 0pssin | |- ( (/) C. ( A i^i B ) <-> E. x ( x e. A /\ x e. B ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | 0pss | |- ( (/) C. ( A i^i B ) <-> ( A i^i B ) =/= (/) ) |
|
2 | ndisj | |- ( ( A i^i B ) =/= (/) <-> E. x ( x e. A /\ x e. B ) ) |
|
3 | 1 2 | bitri | |- ( (/) C. ( A i^i B ) <-> E. x ( x e. A /\ x e. B ) ) |