Metamath Proof Explorer


Theorem fveq1d

Description: Equality deduction for function value. (Contributed by NM, 2-Sep-2003)

Ref Expression
Hypothesis fveq1d.1 φF=G
Assertion fveq1d φFA=GA

Proof

Step Hyp Ref Expression
1 fveq1d.1 φF=G
2 fveq1 F=GFA=GA
3 1 2 syl φFA=GA