Metamath Proof Explorer


Theorem a1i14

Description: Add two antecedents to a wff. (Contributed by Jeff Hankins, 4-Aug-2009)

Ref Expression
Hypothesis a1i14.1
|- ( ps -> ( ch -> ta ) )
Assertion a1i14
|- ( ph -> ( ps -> ( ch -> ( th -> ta ) ) ) )

Proof

Step Hyp Ref Expression
1 a1i14.1
 |-  ( ps -> ( ch -> ta ) )
2 1 a1dd
 |-  ( ps -> ( ch -> ( th -> ta ) ) )
3 2 a1i
 |-  ( ph -> ( ps -> ( ch -> ( th -> ta ) ) ) )