Metamath Proof Explorer


Theorem oveqi

Description: Equality inference for operation value. (Contributed by NM, 24-Nov-2007)

Ref Expression
Hypothesis oveq1i.1
|- A = B
Assertion oveqi
|- ( C A D ) = ( C B D )

Proof

Step Hyp Ref Expression
1 oveq1i.1
 |-  A = B
2 oveq
 |-  ( A = B -> ( C A D ) = ( C B D ) )
3 1 2 ax-mp
 |-  ( C A D ) = ( C B D )