Description: Equality deduction for product. (Contributed by Scott Fenton, 4-Dec-2017)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | prodeq12dv.1 | |- ( ph -> A = B ) |
|
| prodeq12dv.2 | |- ( ( ph /\ k e. A ) -> C = D ) |
||
| Assertion | prodeq12dv | |- ( ph -> prod_ k e. A C = prod_ k e. B D ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | prodeq12dv.1 | |- ( ph -> A = B ) |
|
| 2 | prodeq12dv.2 | |- ( ( ph /\ k e. A ) -> C = D ) |
|
| 3 | 2 | prodeq2dv | |- ( ph -> prod_ k e. A C = prod_ k e. A D ) |
| 4 | 1 | prodeq1d | |- ( ph -> prod_ k e. A D = prod_ k e. B D ) |
| 5 | 3 4 | eqtrd | |- ( ph -> prod_ k e. A C = prod_ k e. B D ) |