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