Description: Equality deduction for operation value. (Contributed by NM, 13-Mar-1995) (Proof shortened by Andrew Salmon, 22-Oct-2011)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | oveq1d.1 | |- ( ph -> A = B ) |
|
| oveq12d.2 | |- ( ph -> C = D ) |
||
| Assertion | oveq12d | |- ( ph -> ( A F C ) = ( B F D ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | oveq1d.1 | |- ( ph -> A = B ) |
|
| 2 | oveq12d.2 | |- ( ph -> C = D ) |
|
| 3 | oveq12 | |- ( ( A = B /\ C = D ) -> ( A F C ) = ( B F D ) ) |
|
| 4 | 1 2 3 | syl2anc | |- ( ph -> ( A F C ) = ( B F D ) ) |