Metamath Proof Explorer


Theorem nf5rd

Description: Consequence of the definition of not-free in a context. (Contributed by Mario Carneiro, 11-Aug-2016)

Ref Expression
Hypothesis nf5rd.1
|- ( ph -> F/ x ps )
Assertion nf5rd
|- ( ph -> ( ps -> A. x ps ) )

Proof

Step Hyp Ref Expression
1 nf5rd.1
 |-  ( ph -> F/ x ps )
2 nf5r
 |-  ( F/ x ps -> ( ps -> A. x ps ) )
3 1 2 syl
 |-  ( ph -> ( ps -> A. x ps ) )