Theorem syl3c 63

Description: A syllogism inference combined with contraction. (Contributed by Alan Sare, 7-Jul-2011.)

Hypotheses

Ref	Expression
syl3c.1	|- ( ph -> ps )
syl3c.2	|- ( ph -> ch )
syl3c.3	|- ( ph -> th )
syl3c.4	|- ( ps -> ( ch -> ( th -> ta ) ) )

Assertion

Ref	Expression
syl3c	|- ( ph -> ta )

Proof of Theorem syl3c

Step	Hyp	Ref	Expression
1		syl3c.3	. 2 |- ( ph -> th )
2		syl3c.1	. . 3 |- ( ph -> ps )
3		syl3c.2	. . 3 |- ( ph -> ch )
4		syl3c.4	. . 3 |- ( ps -> ( ch -> ( th -> ta ) ) )
5	2, 3, 4	sylc 62	. 2 |- ( ph -> ( th -> ta ) )
6	1, 5	mpd 13	1 |- ( ph -> ta )

Syntax hints:   -> wi 4

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

This theorem is referenced by:  bilukdc  1407  disjiun  4029  tfrlem1  6375  tfrcl  6431  mkvprop  7233  ccfunen  7347  caucvgprprlemval  7772  suplocsrlem  7892  peano5uzti  9451  seqf1oglem2  10629  zfz1iso  10950  lcmneg  12267  prmind2  12313  pcfac  12544  cnmpt12  14607  cnmpt22  14614  limccnp2lem  14996  2sqlem6  15445  2sqlem8  15448  sbthom  15757