Description: Equality theorem for intersection of two classes. (Contributed by NM, 26-Dec-1993)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | ineq2 | |- ( A = B -> ( C i^i A ) = ( C i^i B ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ineq1 | |- ( A = B -> ( A i^i C ) = ( B i^i C ) ) |
|
| 2 | incom | |- ( C i^i A ) = ( A i^i C ) |
|
| 3 | incom | |- ( C i^i B ) = ( B i^i C ) |
|
| 4 | 1 2 3 | 3eqtr4g | |- ( A = B -> ( C i^i A ) = ( C i^i B ) ) |