Metamath Proof Explorer


Theorem oveq12

Description: Equality theorem for operation value. (Contributed by NM, 16-Jul-1995)

Ref Expression
Assertion oveq12 A = B C = D A F C = B F D

Proof

Step Hyp Ref Expression
1 oveq1 A = B A F C = B F C
2 oveq2 C = D B F C = B F D
3 1 2 sylan9eq A = B C = D A F C = B F D