Theorem pm2.43a 51

Description: Inference absorbing redundant antecedent. (Contributed by NM, 7-Nov-1995.) (Proof shortened by O'Cat, 28-Nov-2008.)

Hypothesis

Ref	Expression
pm2.43a.1	|- ( ps -> ( ph -> ( ps -> ch ) ) )

Assertion

Ref	Expression
pm2.43a	|- ( ps -> ( ph -> ch ) )

Proof of Theorem pm2.43a

Step	Hyp	Ref	Expression
1		id 19	. 2 |- ( ps -> ps )
2		pm2.43a.1	. 2 |- ( ps -> ( ph -> ( ps -> ch ) ) )
3	1, 2	mpid 42	1 |- ( ps -> ( ph -> ch ) )

Syntax hints:   -> wi 4

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7

This theorem is referenced by:  pm2.43b  52  rspc  2837  rspc2gv  2855  intss1  3861  fvopab3ig  5592  nndi  6489  uzind2  9367  ssfzo12  10226  fiinopn  13543