Theorem syld3an1 1279

Description: A syllogism inference. (Contributed by NM, 7-Jul-2008.)

Hypotheses

Ref	Expression
syld3an1.1	|- ( ( ch /\ ps /\ th ) -> ph )
syld3an1.2	|- ( ( ph /\ ps /\ th ) -> ta )

Assertion

Ref	Expression
syld3an1	|- ( ( ch /\ ps /\ th ) -> ta )

Proof of Theorem syld3an1

Step	Hyp	Ref	Expression
1		syld3an1.1	. . . 4 |- ( ( ch /\ ps /\ th ) -> ph )
2	1	3com13 1203	. . 3 |- ( ( th /\ ps /\ ch ) -> ph )
3		syld3an1.2	. . . 4 |- ( ( ph /\ ps /\ th ) -> ta )
4	3	3com13 1203	. . 3 |- ( ( th /\ ps /\ ph ) -> ta )
5	2, 4	syld3an3 1278	. 2 |- ( ( th /\ ps /\ ch ) -> ta )
6	5	3com13 1203	1 |- ( ( ch /\ ps /\ th ) -> ta )

Syntax hints:   -> wi 4   /\ w3a 973

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107

This theorem depends on definitions:  df-bi 116  df-3an 975

This theorem is referenced by:  tfrcllembacc  6334  npncan  8140  nnpcan  8142  ppncan  8161  muldivdirap  8624  div2negap  8652  ltmuldiv  8790  mulqmod0  10286