Metamath Proof Explorer


Theorem fveq12i

Description: Equality deduction for function value. (Contributed by FL, 27-Jun-2014)

Ref Expression
Hypotheses fveq12i.1 𝐹 = 𝐺
fveq12i.2 𝐴 = 𝐵
Assertion fveq12i ( 𝐹𝐴 ) = ( 𝐺𝐵 )

Proof

Step Hyp Ref Expression
1 fveq12i.1 𝐹 = 𝐺
2 fveq12i.2 𝐴 = 𝐵
3 1 fveq1i ( 𝐹𝐴 ) = ( 𝐺𝐴 )
4 2 fveq2i ( 𝐺𝐴 ) = ( 𝐺𝐵 )
5 3 4 eqtri ( 𝐹𝐴 ) = ( 𝐺𝐵 )