Theorem xrlelttr 8876

Description: Transitive law for ordering on extended reals. (Contributed by NM, 19-Jan-2006.)

Assertion

Ref	Expression
xrlelttr	|- ( ( A e. RR* /\ B e. RR* /\ C e. RR* ) -> ( ( A <_ B /\ B < C ) -> A < C ) )

Proof of Theorem xrlelttr

Step	Hyp	Ref	Expression
1		simprl 497	. . . . 5 |- ( ( ( A e. RR* /\ B e. RR* /\ C e. RR* ) /\ ( A <_ B /\ B < C ) ) -> A <_ B )
2		simpl1 941	. . . . . 6 |- ( ( ( A e. RR* /\ B e. RR* /\ C e. RR* ) /\ ( A <_ B /\ B < C ) ) -> A e. RR* )
3		simpl2 942	. . . . . 6 |- ( ( ( A e. RR* /\ B e. RR* /\ C e. RR* ) /\ ( A <_ B /\ B < C ) ) -> B e. RR* )
4		xrlenlt 7177	. . . . . 6 |- ( ( A e. RR* /\ B e. RR* ) -> ( A <_ B <-> -. B < A ) )
5	2, 3, 4	syl2anc 403	. . . . 5 |- ( ( ( A e. RR* /\ B e. RR* /\ C e. RR* ) /\ ( A <_ B /\ B < C ) ) -> ( A <_ B <-> -. B < A ) )
6	1, 5	mpbid 145	. . . 4 |- ( ( ( A e. RR* /\ B e. RR* /\ C e. RR* ) /\ ( A <_ B /\ B < C ) ) -> -. B < A )
7	6	pm2.21d 581	. . 3 |- ( ( ( A e. RR* /\ B e. RR* /\ C e. RR* ) /\ ( A <_ B /\ B < C ) ) -> ( B < A -> A < C ) )
8		idd 21	. . 3 |- ( ( ( A e. RR* /\ B e. RR* /\ C e. RR* ) /\ ( A <_ B /\ B < C ) ) -> ( A < C -> A < C ) )
9		simprr 498	. . . 4 |- ( ( ( A e. RR* /\ B e. RR* /\ C e. RR* ) /\ ( A <_ B /\ B < C ) ) -> B < C )
10		simpl3 943	. . . . 5 |- ( ( ( A e. RR* /\ B e. RR* /\ C e. RR* ) /\ ( A <_ B /\ B < C ) ) -> C e. RR* )
11		xrltso 8871	. . . . . 6 |- < Or RR*
12		sowlin 4075	. . . . . 6 |- ( ( < Or RR* /\ ( B e. RR* /\ C e. RR* /\ A e. RR* ) ) -> ( B < C -> ( B < A \/ A < C ) ) )
13	11, 12	mpan 414	. . . . 5 |- ( ( B e. RR* /\ C e. RR* /\ A e. RR* ) -> ( B < C -> ( B < A \/ A < C ) ) )
14	3, 10, 2, 13	syl3anc 1169	. . . 4 |- ( ( ( A e. RR* /\ B e. RR* /\ C e. RR* ) /\ ( A <_ B /\ B < C ) ) -> ( B < C -> ( B < A \/ A < C ) ) )
15	9, 14	mpd 13	. . 3 |- ( ( ( A e. RR* /\ B e. RR* /\ C e. RR* ) /\ ( A <_ B /\ B < C ) ) -> ( B < A \/ A < C ) )
16	7, 8, 15	mpjaod 670	. 2 |- ( ( ( A e. RR* /\ B e. RR* /\ C e. RR* ) /\ ( A <_ B /\ B < C ) ) -> A < C )
17	16	ex 113	1 |- ( ( A e. RR* /\ B e. RR* /\ C e. RR* ) -> ( ( A <_ B /\ B < C ) -> A < C ) )

Syntax hints:   -. wn 3   -> wi 4   /\ wa 102   <-> wb 103   \/ wo 661   /\ w3a 919   e. wcel 1433   class class class wbr 3785   Or wor 4050   RR*cxr 7152   < clt 7153   <_ cle 7154

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-in1 576  ax-in2 577  ax-io 662  ax-5 1376  ax-7 1377  ax-gen 1378  ax-ie1 1422  ax-ie2 1423  ax-8 1435  ax-10 1436  ax-11 1437  ax-i12 1438  ax-bndl 1439  ax-4 1440  ax-13 1444  ax-14 1445  ax-17 1459  ax-i9 1463  ax-ial 1467  ax-i5r 1468  ax-ext 2063  ax-sep 3896  ax-pow 3948  ax-pr 3964  ax-un 4188  ax-setind 4280  ax-cnex 7067  ax-resscn 7068  ax-pre-ltirr 7088  ax-pre-ltwlin 7089  ax-pre-lttrn 7090

This theorem depends on definitions:  df-bi 115  df-3or 920  df-3an 921  df-tru 1287  df-fal 1290  df-nf 1390  df-sb 1686  df-eu 1944  df-mo 1945  df-clab 2068  df-cleq 2074  df-clel 2077  df-nfc 2208  df-ne 2246  df-nel 2340  df-ral 2353  df-rex 2354  df-rab 2357  df-v 2603  df-dif 2975  df-un 2977  df-in 2979  df-ss 2986  df-pw 3384  df-sn 3404  df-pr 3405  df-op 3407  df-uni 3602  df-br 3786  df-opab 3840  df-po 4051  df-iso 4052  df-xp 4369  df-cnv 4371  df-pnf 7155  df-mnf 7156  df-xr 7157  df-ltxr 7158  df-le 7159

This theorem is referenced by:  xrlelttrd  8880  xrre  8887  xrre2  8888  iooss1  8939  iccssioo  8965  iccssico  8968  iocssioo  8986  ioossioo  8988  ico0  9270