Description: Equality theorem for indexed union, deduction version. (Contributed by Drahflow, 22-Oct-2015)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | iuneq1d.1 | |- ( ph -> A = B ) | |
| Assertion | iuneq1d | |- ( ph -> U_ x e. A C = U_ x e. B C ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | iuneq1d.1 | |- ( ph -> A = B ) | |
| 2 | iuneq1 | |- ( A = B -> U_ x e. A C = U_ x e. B C ) | |
| 3 | 1 2 | syl | |- ( ph -> U_ x e. A C = U_ x e. B C ) |