Metamath Proof Explorer


Theorem afv2eq2

Description: Equality theorem for function value, analogous to fveq2 . (Contributed by AV, 4-Sep-2022)

Ref Expression
Assertion afv2eq2 ( 𝐴 = 𝐵 → ( 𝐹 '''' 𝐴 ) = ( 𝐹 '''' 𝐵 ) )

Proof

Step Hyp Ref Expression
1 eqidd ( 𝐴 = 𝐵𝐹 = 𝐹 )
2 id ( 𝐴 = 𝐵𝐴 = 𝐵 )
3 1 2 afv2eq12d ( 𝐴 = 𝐵 → ( 𝐹 '''' 𝐴 ) = ( 𝐹 '''' 𝐵 ) )