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 ) ) |