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 ) )