Metamath Proof Explorer


Theorem 3imtr3g

Description: More general version of 3imtr3i . Useful for converting definitions in a formula. (Contributed by NM, 20-May-1996) (Proof shortened by Wolf Lammen, 20-Dec-2013)

Ref Expression
Hypotheses 3imtr3g.1
|- ( ph -> ( ps -> ch ) )
3imtr3g.2
|- ( ps <-> th )
3imtr3g.3
|- ( ch <-> ta )
Assertion 3imtr3g
|- ( ph -> ( th -> ta ) )

Proof

Step Hyp Ref Expression
1 3imtr3g.1
 |-  ( ph -> ( ps -> ch ) )
2 3imtr3g.2
 |-  ( ps <-> th )
3 3imtr3g.3
 |-  ( ch <-> ta )
4 2 1 syl5bir
 |-  ( ph -> ( th -> ch ) )
5 4 3 syl6ib
 |-  ( ph -> ( th -> ta ) )