Metamath Proof Explorer


Theorem hbimd

Description: Deduction form of bound-variable hypothesis builder hbim . (Contributed by NM, 14-May-1993) (Proof shortened by Wolf Lammen, 3-Jan-2018)

Ref Expression
Hypotheses hbimd.1
|- ( ph -> A. x ph )
hbimd.2
|- ( ph -> ( ps -> A. x ps ) )
hbimd.3
|- ( ph -> ( ch -> A. x ch ) )
Assertion hbimd
|- ( ph -> ( ( ps -> ch ) -> A. x ( ps -> ch ) ) )

Proof

Step Hyp Ref Expression
1 hbimd.1
 |-  ( ph -> A. x ph )
2 hbimd.2
 |-  ( ph -> ( ps -> A. x ps ) )
3 hbimd.3
 |-  ( ph -> ( ch -> A. x ch ) )
4 1 2 nf5dh
 |-  ( ph -> F/ x ps )
5 1 3 nf5dh
 |-  ( ph -> F/ x ch )
6 4 5 nfimd
 |-  ( ph -> F/ x ( ps -> ch ) )
7 6 nf5rd
 |-  ( ph -> ( ( ps -> ch ) -> A. x ( ps -> ch ) ) )