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Theorem mnfltpnf 5517
Description: Minus infinity is less than plus infinity.
Assertion
Ref Expression
mnfltpnf |- -oo < +oo

Proof of Theorem mnfltpnf
StepHypRef Expression
1 eqid 1468 . . . 4 |- -oo = -oo
2 eqid 1468 . . . 4 |- +oo = +oo
3 olc 268 . . . 4 |- (( -oo = -oo /\ +oo = +oo) -> ((( -oo e. RR /\ +oo e. RR) /\ -oo <R +oo) \/ ( -oo = -oo /\ +oo = +oo)))
41, 2, 3mp2an 695 . . 3 |- ((( -oo e. RR /\ +oo e. RR) /\ -oo <R +oo) \/ ( -oo = -oo /\ +oo = +oo))
54orci 270 . 2 |- (((( -oo e. RR /\ +oo e. RR) /\ -oo <R +oo) \/ ( -oo = -oo /\ +oo = +oo)) \/ (( -oo e. RR /\ +oo = +oo) \/ ( -oo = -oo /\ +oo e. RR)))
6 mnfxr 5466 . . 3 |- -oo e. RR*
7 pnfxr 5465 . . 3 |- +oo e. RR*
8 ltxrt 5467 . . 3 |- (( -oo e. RR* /\ +oo e. RR*) -> ( -oo < +oo <-> (((( -oo e. RR /\ +oo e. RR) /\ -oo <R +oo) \/ ( -oo = -oo /\ +oo = +oo)) \/ (( -oo e. RR /\ +oo = +oo) \/ ( -oo = -oo /\ +oo e. RR)))))
96, 7, 8mp2an 695 . 2 |- ( -oo < +oo <-> (((( -oo e. RR /\ +oo e. RR) /\ -oo <R +oo) \/ ( -oo = -oo /\ +oo = +oo)) \/ (( -oo e. RR /\ +oo = +oo) \/ ( -oo = -oo /\ +oo e. RR))))
105, 9mpbir 190 1 |- -oo < +oo
Colors of variables: wff set class
Syntax hints:   <-> wb 146   \/ wo 222   /\ wa 223   = wceq 953   e. wcel 955   class class class wbr 2609  RRcr 5205   <R cltrr 5210   +oocpnf 5455   -oocmnf 5456  RR*cxr 5457   < clt 5458
This theorem is referenced by:  mnfltxrt 5518  xrlttrit 5525  xrlttrt 5526
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-7 959  ax-gen 960  ax-8 961  ax-9 962  ax-10 963  ax-11 964  ax-12 965  ax-13 966  ax-14 967  ax-17 968  ax-4 970  ax-5o 972  ax-6o 975  ax-9o 1119  ax-10o 1136  ax-16 1206  ax-11o 1213  ax-ext 1452  ax-rep 2683  ax-sep 2693  ax-nul 2700  ax-pow 2732  ax-pr 2769  ax-un 2857  ax-inf2 4597
This theorem depends on definitions:  df-bi 147  df-or 224  df-an 225  df-3or 774  df-3an 775  df-ex 978  df-sb 1168  df-eu 1375  df-mo 1376  df-clab 1457  df-cleq 1462  df-clel 1465  df-ne 1579  df-ral 1641  df-rex 1642  df-v 1803  df-dif 2039  df-un 2040  df-in 2041  df-ss 2043  df-pss 2045  df-nul 2271  df-if 2352  df-pw 2392  df-sn 2402  df-pr 2403  df-tp 2405  df-op 2406  df-uni 2494  df-br 2610  df-opab 2657  df-tr 2671  df-eprel 2821  df-id 2824  df-po 2831  df-so 2841  df-fr 2907  df-we 2924  df-ord 2941  df-on 2942  df-lim 2943  df-suc 2944  df-om 3122  df-xp 3174  df-rel 3175  df-cnv 3176  df-co 3177  df-dm 3178  df-rn 3179  df-res 3180  df-ima 3181  df-fun 3182  df-fn 3183  df-qs 4250  df-ni 4972  df-nq 5010  df-np 5058  df-nr 5139  df-c 5212  df-pnf 5459  df-mnf 5460  df-xr 5461  df-ltxr 5462
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