Metamath Proof Explorer


Theorem oveq1

Description: Equality theorem for operation value. (Contributed by NM, 28-Feb-1995)

Ref Expression
Assertion oveq1 A = B A F C = B F C

Proof

Step Hyp Ref Expression
1 opeq1 A = B A C = B C
2 1 fveq2d A = B F A C = F B C
3 df-ov A F C = F A C
4 df-ov B F C = F B C
5 2 3 4 3eqtr4g A = B A F C = B F C