Theorem xrlttr 9917

Description: Ordering on the extended reals is transitive. (Contributed by NM, 15-Oct-2005.)

Assertion

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

Proof of Theorem xrlttr

Step	Hyp	Ref	Expression
1		elxr 9898	. 2 |- ( A e. RR* <-> ( A e. RR \/ A = +oo \/ A = -oo ) )
2		elxr 9898	. . 3 |- ( C e. RR* <-> ( C e. RR \/ C = +oo \/ C = -oo ) )
3		elxr 9898	. . . . . . . . 9 |- ( B e. RR* <-> ( B e. RR \/ B = +oo \/ B = -oo ) )
4		lttr 8146	. . . . . . . . . . . 12 |- ( ( A e. RR /\ B e. RR /\ C e. RR ) -> ( ( A < B /\ B < C ) -> A < C ) )
5	4	3expa 1206	. . . . . . . . . . 11 |- ( ( ( A e. RR /\ B e. RR ) /\ C e. RR ) -> ( ( A < B /\ B < C ) -> A < C ) )
6	5	an32s 568	. . . . . . . . . 10 |- ( ( ( A e. RR /\ C e. RR ) /\ B e. RR ) -> ( ( A < B /\ B < C ) -> A < C ) )
7		rexr 8118	. . . . . . . . . . . . . . . 16 |- ( C e. RR -> C e. RR* )
8		pnfnlt 9909	. . . . . . . . . . . . . . . 16 |- ( C e. RR* -> -. +oo < C )
9	7, 8	syl 14	. . . . . . . . . . . . . . 15 |- ( C e. RR -> -. +oo < C )
10	9	adantr 276	. . . . . . . . . . . . . 14 |- ( ( C e. RR /\ B = +oo ) -> -. +oo < C )
11		breq1 4047	. . . . . . . . . . . . . . 15 |- ( B = +oo -> ( B < C <-> +oo < C ) )
12	11	adantl 277	. . . . . . . . . . . . . 14 |- ( ( C e. RR /\ B = +oo ) -> ( B < C <-> +oo < C ) )
13	10, 12	mtbird 675	. . . . . . . . . . . . 13 |- ( ( C e. RR /\ B = +oo ) -> -. B < C )
14	13	pm2.21d 620	. . . . . . . . . . . 12 |- ( ( C e. RR /\ B = +oo ) -> ( B < C -> A < C ) )
15	14	adantll 476	. . . . . . . . . . 11 |- ( ( ( A e. RR /\ C e. RR ) /\ B = +oo ) -> ( B < C -> A < C ) )
16	15	adantld 278	. . . . . . . . . 10 |- ( ( ( A e. RR /\ C e. RR ) /\ B = +oo ) -> ( ( A < B /\ B < C ) -> A < C ) )
17		rexr 8118	. . . . . . . . . . . . . . . 16 |- ( A e. RR -> A e. RR* )
18		nltmnf 9910	. . . . . . . . . . . . . . . 16 |- ( A e. RR* -> -. A < -oo )
19	17, 18	syl 14	. . . . . . . . . . . . . . 15 |- ( A e. RR -> -. A < -oo )
20	19	adantr 276	. . . . . . . . . . . . . 14 |- ( ( A e. RR /\ B = -oo ) -> -. A < -oo )
21		breq2 4048	. . . . . . . . . . . . . . 15 |- ( B = -oo -> ( A < B <-> A < -oo ) )
22	21	adantl 277	. . . . . . . . . . . . . 14 |- ( ( A e. RR /\ B = -oo ) -> ( A < B <-> A < -oo ) )
23	20, 22	mtbird 675	. . . . . . . . . . . . 13 |- ( ( A e. RR /\ B = -oo ) -> -. A < B )
24	23	pm2.21d 620	. . . . . . . . . . . 12 |- ( ( A e. RR /\ B = -oo ) -> ( A < B -> A < C ) )
25	24	adantlr 477	. . . . . . . . . . 11 |- ( ( ( A e. RR /\ C e. RR ) /\ B = -oo ) -> ( A < B -> A < C ) )
26	25	adantrd 279	. . . . . . . . . 10 |- ( ( ( A e. RR /\ C e. RR ) /\ B = -oo ) -> ( ( A < B /\ B < C ) -> A < C ) )
27	6, 16, 26	3jaodan 1319	. . . . . . . . 9 |- ( ( ( A e. RR /\ C e. RR ) /\ ( B e. RR \/ B = +oo \/ B = -oo ) ) -> ( ( A < B /\ B < C ) -> A < C ) )
28	3, 27	sylan2b 287	. . . . . . . 8 |- ( ( ( A e. RR /\ C e. RR ) /\ B e. RR* ) -> ( ( A < B /\ B < C ) -> A < C ) )
29	28	an32s 568	. . . . . . 7 |- ( ( ( A e. RR /\ B e. RR* ) /\ C e. RR ) -> ( ( A < B /\ B < C ) -> A < C ) )
30		ltpnf 9902	. . . . . . . . . . 11 |- ( A e. RR -> A < +oo )
31	30	adantr 276	. . . . . . . . . 10 |- ( ( A e. RR /\ C = +oo ) -> A < +oo )
32		breq2 4048	. . . . . . . . . . 11 |- ( C = +oo -> ( A < C <-> A < +oo ) )
33	32	adantl 277	. . . . . . . . . 10 |- ( ( A e. RR /\ C = +oo ) -> ( A < C <-> A < +oo ) )
34	31, 33	mpbird 167	. . . . . . . . 9 |- ( ( A e. RR /\ C = +oo ) -> A < C )
35	34	adantlr 477	. . . . . . . 8 |- ( ( ( A e. RR /\ B e. RR* ) /\ C = +oo ) -> A < C )
36	35	a1d 22	. . . . . . 7 |- ( ( ( A e. RR /\ B e. RR* ) /\ C = +oo ) -> ( ( A < B /\ B < C ) -> A < C ) )
37		nltmnf 9910	. . . . . . . . . . . 12 |- ( B e. RR* -> -. B < -oo )
38	37	adantr 276	. . . . . . . . . . 11 |- ( ( B e. RR* /\ C = -oo ) -> -. B < -oo )
39		breq2 4048	. . . . . . . . . . . 12 |- ( C = -oo -> ( B < C <-> B < -oo ) )
40	39	adantl 277	. . . . . . . . . . 11 |- ( ( B e. RR* /\ C = -oo ) -> ( B < C <-> B < -oo ) )
41	38, 40	mtbird 675	. . . . . . . . . 10 |- ( ( B e. RR* /\ C = -oo ) -> -. B < C )
42	41	pm2.21d 620	. . . . . . . . 9 |- ( ( B e. RR* /\ C = -oo ) -> ( B < C -> A < C ) )
43	42	adantld 278	. . . . . . . 8 |- ( ( B e. RR* /\ C = -oo ) -> ( ( A < B /\ B < C ) -> A < C ) )
44	43	adantll 476	. . . . . . 7 |- ( ( ( A e. RR /\ B e. RR* ) /\ C = -oo ) -> ( ( A < B /\ B < C ) -> A < C ) )
45	29, 36, 44	3jaodan 1319	. . . . . 6 |- ( ( ( A e. RR /\ B e. RR* ) /\ ( C e. RR \/ C = +oo \/ C = -oo ) ) -> ( ( A < B /\ B < C ) -> A < C ) )
46	45	anasss 399	. . . . 5 |- ( ( A e. RR /\ ( B e. RR* /\ ( C e. RR \/ C = +oo \/ C = -oo ) ) ) -> ( ( A < B /\ B < C ) -> A < C ) )
47		pnfnlt 9909	. . . . . . . . . 10 |- ( B e. RR* -> -. +oo < B )
48	47	adantl 277	. . . . . . . . 9 |- ( ( A = +oo /\ B e. RR* ) -> -. +oo < B )
49		breq1 4047	. . . . . . . . . 10 |- ( A = +oo -> ( A < B <-> +oo < B ) )
50	49	adantr 276	. . . . . . . . 9 |- ( ( A = +oo /\ B e. RR* ) -> ( A < B <-> +oo < B ) )
51	48, 50	mtbird 675	. . . . . . . 8 |- ( ( A = +oo /\ B e. RR* ) -> -. A < B )
52	51	pm2.21d 620	. . . . . . 7 |- ( ( A = +oo /\ B e. RR* ) -> ( A < B -> A < C ) )
53	52	adantrd 279	. . . . . 6 |- ( ( A = +oo /\ B e. RR* ) -> ( ( A < B /\ B < C ) -> A < C ) )
54	53	adantrr 479	. . . . 5 |- ( ( A = +oo /\ ( B e. RR* /\ ( C e. RR \/ C = +oo \/ C = -oo ) ) ) -> ( ( A < B /\ B < C ) -> A < C ) )
55		mnflt 9905	. . . . . . . . . . 11 |- ( C e. RR -> -oo < C )
56	55	adantl 277	. . . . . . . . . 10 |- ( ( A = -oo /\ C e. RR ) -> -oo < C )
57		breq1 4047	. . . . . . . . . . 11 |- ( A = -oo -> ( A < C <-> -oo < C ) )
58	57	adantr 276	. . . . . . . . . 10 |- ( ( A = -oo /\ C e. RR ) -> ( A < C <-> -oo < C ) )
59	56, 58	mpbird 167	. . . . . . . . 9 |- ( ( A = -oo /\ C e. RR ) -> A < C )
60	59	a1d 22	. . . . . . . 8 |- ( ( A = -oo /\ C e. RR ) -> ( ( A < B /\ B < C ) -> A < C ) )
61	60	adantlr 477	. . . . . . 7 |- ( ( ( A = -oo /\ B e. RR* ) /\ C e. RR ) -> ( ( A < B /\ B < C ) -> A < C ) )
62		mnfltpnf 9907	. . . . . . . . . 10 |- -oo < +oo
63		breq12 4049	. . . . . . . . . 10 |- ( ( A = -oo /\ C = +oo ) -> ( A < C <-> -oo < +oo ) )
64	62, 63	mpbiri 168	. . . . . . . . 9 |- ( ( A = -oo /\ C = +oo ) -> A < C )
65	64	a1d 22	. . . . . . . 8 |- ( ( A = -oo /\ C = +oo ) -> ( ( A < B /\ B < C ) -> A < C ) )
66	65	adantlr 477	. . . . . . 7 |- ( ( ( A = -oo /\ B e. RR* ) /\ C = +oo ) -> ( ( A < B /\ B < C ) -> A < C ) )
67	43	adantll 476	. . . . . . 7 |- ( ( ( A = -oo /\ B e. RR* ) /\ C = -oo ) -> ( ( A < B /\ B < C ) -> A < C ) )
68	61, 66, 67	3jaodan 1319	. . . . . 6 |- ( ( ( A = -oo /\ B e. RR* ) /\ ( C e. RR \/ C = +oo \/ C = -oo ) ) -> ( ( A < B /\ B < C ) -> A < C ) )
69	68	anasss 399	. . . . 5 |- ( ( A = -oo /\ ( B e. RR* /\ ( C e. RR \/ C = +oo \/ C = -oo ) ) ) -> ( ( A < B /\ B < C ) -> A < C ) )
70	46, 54, 69	3jaoian 1318	. . . 4 |- ( ( ( A e. RR \/ A = +oo \/ A = -oo ) /\ ( B e. RR* /\ ( C e. RR \/ C = +oo \/ C = -oo ) ) ) -> ( ( A < B /\ B < C ) -> A < C ) )
71	70	3impb 1202	. . 3 |- ( ( ( A e. RR \/ A = +oo \/ A = -oo ) /\ B e. RR* /\ ( C e. RR \/ C = +oo \/ C = -oo ) ) -> ( ( A < B /\ B < C ) -> A < C ) )
72	2, 71	syl3an3b 1288	. 2 |- ( ( ( A e. RR \/ A = +oo \/ A = -oo ) /\ B e. RR* /\ C e. RR* ) -> ( ( A < B /\ B < C ) -> A < C ) )
73	1, 72	syl3an1b 1286	1 |- ( ( A e. RR* /\ B e. RR* /\ C e. RR* ) -> ( ( A < B /\ B < C ) -> A < C ) )

Syntax hints:   -. wn 3   -> wi 4   /\ wa 104   <-> wb 105   \/ w3o 980   /\ w3a 981   = wceq 1373   e. wcel 2176   class class class wbr 4044   RRcr 7924   +oocpnf 8104   -oocmnf 8105   RR*cxr 8106   < clt 8107

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 615  ax-in2 616  ax-io 711  ax-5 1470  ax-7 1471  ax-gen 1472  ax-ie1 1516  ax-ie2 1517  ax-8 1527  ax-10 1528  ax-11 1529  ax-i12 1530  ax-bndl 1532  ax-4 1533  ax-17 1549  ax-i9 1553  ax-ial 1557  ax-i5r 1558  ax-13 2178  ax-14 2179  ax-ext 2187  ax-sep 4162  ax-pow 4218  ax-pr 4253  ax-un 4480  ax-setind 4585  ax-cnex 8016  ax-resscn 8017  ax-pre-lttrn 8039

This theorem depends on definitions:  df-bi 117  df-3or 982  df-3an 983  df-tru 1376  df-fal 1379  df-nf 1484  df-sb 1786  df-eu 2057  df-mo 2058  df-clab 2192  df-cleq 2198  df-clel 2201  df-nfc 2337  df-ne 2377  df-nel 2472  df-ral 2489  df-rex 2490  df-rab 2493  df-v 2774  df-dif 3168  df-un 3170  df-in 3172  df-ss 3179  df-pw 3618  df-sn 3639  df-pr 3640  df-op 3642  df-uni 3851  df-br 4045  df-opab 4106  df-xp 4681  df-pnf 8109  df-mnf 8110  df-xr 8111  df-ltxr 8112

This theorem is referenced by:  xrltso  9918  xrlttrd  9931  ioo0  10402