Metamath Proof Explorer


Theorem fveq2d

Description: Equality deduction for function value. (Contributed by NM, 29-May-1999)

Ref Expression
Hypothesis fveq2d.1 ( 𝜑𝐴 = 𝐵 )
Assertion fveq2d ( 𝜑 → ( 𝐹𝐴 ) = ( 𝐹𝐵 ) )

Proof

Step Hyp Ref Expression
1 fveq2d.1 ( 𝜑𝐴 = 𝐵 )
2 fveq2 ( 𝐴 = 𝐵 → ( 𝐹𝐴 ) = ( 𝐹𝐵 ) )
3 1 2 syl ( 𝜑 → ( 𝐹𝐴 ) = ( 𝐹𝐵 ) )