Metamath Proof Explorer


Theorem fveq2d

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

Ref Expression
Hypothesis fveq2d.1 ⊢ ( 𝜑 → 𝐴 = 𝐵 )
Assertion fveq2d ( 𝜑 → ( 𝐹 ‘ 𝐴 ) = ( 𝐹 ‘ 𝐵 ) )

Proof

Step Hyp Ref Expression
1 fveq2d.1 ⊢ ( 𝜑 → 𝐴 = 𝐵 )
2 fveq2 ⊢ ( 𝐴 = 𝐵 → ( 𝐹 ‘ 𝐴 ) = ( 𝐹 ‘ 𝐵 ) )
3 1 2 syl ⊢ ( 𝜑 → ( 𝐹 ‘ 𝐴 ) = ( 𝐹 ‘ 𝐵 ) )