Metamath Proof Explorer


Theorem fveleq

Description: Please add description here. (Contributed by Jeff Hoffman, 12-Feb-2008)

Ref Expression
Assertion fveleq ( 𝐴 = 𝐵 → ( ( 𝜑 → ( 𝐹𝐴 ) ∈ 𝑃 ) ↔ ( 𝜑 → ( 𝐹𝐵 ) ∈ 𝑃 ) ) )

Proof

Step Hyp Ref Expression
1 fveq2 ( 𝐴 = 𝐵 → ( 𝐹𝐴 ) = ( 𝐹𝐵 ) )
2 1 eleq1d ( 𝐴 = 𝐵 → ( ( 𝐹𝐴 ) ∈ 𝑃 ↔ ( 𝐹𝐵 ) ∈ 𝑃 ) )
3 2 imbi2d ( 𝐴 = 𝐵 → ( ( 𝜑 → ( 𝐹𝐴 ) ∈ 𝑃 ) ↔ ( 𝜑 → ( 𝐹𝐵 ) ∈ 𝑃 ) ) )