Description: The intersection of the empty set with a class is the empty set. (Contributed by Glauco Siliprandi, 17-Aug-2020)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | 0in | |- ( (/) i^i A ) = (/) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | incom | |- ( (/) i^i A ) = ( A i^i (/) ) |
|
| 2 | in0 | |- ( A i^i (/) ) = (/) |
|
| 3 | 1 2 | eqtri | |- ( (/) i^i A ) = (/) |