MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  xrltnsym Structured version   Visualization version   GIF version

Theorem xrltnsym 13088
Description: Ordering on the extended reals is not symmetric. (Contributed by NM, 15-Oct-2005.)
Assertion
Ref Expression
xrltnsym ((𝐴 ∈ ℝ*𝐵 ∈ ℝ*) → (𝐴 < 𝐵 → ¬ 𝐵 < 𝐴))

Proof of Theorem xrltnsym
StepHypRef Expression
1 elxr 13067 . 2 (𝐴 ∈ ℝ* ↔ (𝐴 ∈ ℝ ∨ 𝐴 = +∞ ∨ 𝐴 = -∞))
2 elxr 13067 . 2 (𝐵 ∈ ℝ* ↔ (𝐵 ∈ ℝ ∨ 𝐵 = +∞ ∨ 𝐵 = -∞))
3 ltnsym 11244 . . . 4 ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 < 𝐵 → ¬ 𝐵 < 𝐴))
4 rexr 11191 . . . . . . . 8 (𝐴 ∈ ℝ → 𝐴 ∈ ℝ*)
5 pnfnlt 13079 . . . . . . . 8 (𝐴 ∈ ℝ* → ¬ +∞ < 𝐴)
64, 5syl 17 . . . . . . 7 (𝐴 ∈ ℝ → ¬ +∞ < 𝐴)
76adantr 480 . . . . . 6 ((𝐴 ∈ ℝ ∧ 𝐵 = +∞) → ¬ +∞ < 𝐴)
8 breq1 5088 . . . . . . 7 (𝐵 = +∞ → (𝐵 < 𝐴 ↔ +∞ < 𝐴))
98adantl 481 . . . . . 6 ((𝐴 ∈ ℝ ∧ 𝐵 = +∞) → (𝐵 < 𝐴 ↔ +∞ < 𝐴))
107, 9mtbird 325 . . . . 5 ((𝐴 ∈ ℝ ∧ 𝐵 = +∞) → ¬ 𝐵 < 𝐴)
1110a1d 25 . . . 4 ((𝐴 ∈ ℝ ∧ 𝐵 = +∞) → (𝐴 < 𝐵 → ¬ 𝐵 < 𝐴))
12 nltmnf 13080 . . . . . . . 8 (𝐴 ∈ ℝ* → ¬ 𝐴 < -∞)
134, 12syl 17 . . . . . . 7 (𝐴 ∈ ℝ → ¬ 𝐴 < -∞)
1413adantr 480 . . . . . 6 ((𝐴 ∈ ℝ ∧ 𝐵 = -∞) → ¬ 𝐴 < -∞)
15 breq2 5089 . . . . . . 7 (𝐵 = -∞ → (𝐴 < 𝐵𝐴 < -∞))
1615adantl 481 . . . . . 6 ((𝐴 ∈ ℝ ∧ 𝐵 = -∞) → (𝐴 < 𝐵𝐴 < -∞))
1714, 16mtbird 325 . . . . 5 ((𝐴 ∈ ℝ ∧ 𝐵 = -∞) → ¬ 𝐴 < 𝐵)
1817pm2.21d 121 . . . 4 ((𝐴 ∈ ℝ ∧ 𝐵 = -∞) → (𝐴 < 𝐵 → ¬ 𝐵 < 𝐴))
193, 11, 183jaodan 1434 . . 3 ((𝐴 ∈ ℝ ∧ (𝐵 ∈ ℝ ∨ 𝐵 = +∞ ∨ 𝐵 = -∞)) → (𝐴 < 𝐵 → ¬ 𝐵 < 𝐴))
20 pnfnlt 13079 . . . . . . 7 (𝐵 ∈ ℝ* → ¬ +∞ < 𝐵)
2120adantl 481 . . . . . 6 ((𝐴 = +∞ ∧ 𝐵 ∈ ℝ*) → ¬ +∞ < 𝐵)
22 breq1 5088 . . . . . . 7 (𝐴 = +∞ → (𝐴 < 𝐵 ↔ +∞ < 𝐵))
2322adantr 480 . . . . . 6 ((𝐴 = +∞ ∧ 𝐵 ∈ ℝ*) → (𝐴 < 𝐵 ↔ +∞ < 𝐵))
2421, 23mtbird 325 . . . . 5 ((𝐴 = +∞ ∧ 𝐵 ∈ ℝ*) → ¬ 𝐴 < 𝐵)
2524pm2.21d 121 . . . 4 ((𝐴 = +∞ ∧ 𝐵 ∈ ℝ*) → (𝐴 < 𝐵 → ¬ 𝐵 < 𝐴))
262, 25sylan2br 596 . . 3 ((𝐴 = +∞ ∧ (𝐵 ∈ ℝ ∨ 𝐵 = +∞ ∨ 𝐵 = -∞)) → (𝐴 < 𝐵 → ¬ 𝐵 < 𝐴))
27 rexr 11191 . . . . . . . 8 (𝐵 ∈ ℝ → 𝐵 ∈ ℝ*)
28 nltmnf 13080 . . . . . . . 8 (𝐵 ∈ ℝ* → ¬ 𝐵 < -∞)
2927, 28syl 17 . . . . . . 7 (𝐵 ∈ ℝ → ¬ 𝐵 < -∞)
3029adantl 481 . . . . . 6 ((𝐴 = -∞ ∧ 𝐵 ∈ ℝ) → ¬ 𝐵 < -∞)
31 breq2 5089 . . . . . . 7 (𝐴 = -∞ → (𝐵 < 𝐴𝐵 < -∞))
3231adantr 480 . . . . . 6 ((𝐴 = -∞ ∧ 𝐵 ∈ ℝ) → (𝐵 < 𝐴𝐵 < -∞))
3330, 32mtbird 325 . . . . 5 ((𝐴 = -∞ ∧ 𝐵 ∈ ℝ) → ¬ 𝐵 < 𝐴)
3433a1d 25 . . . 4 ((𝐴 = -∞ ∧ 𝐵 ∈ ℝ) → (𝐴 < 𝐵 → ¬ 𝐵 < 𝐴))
35 mnfxr 11202 . . . . . . . 8 -∞ ∈ ℝ*
36 pnfnlt 13079 . . . . . . . 8 (-∞ ∈ ℝ* → ¬ +∞ < -∞)
3735, 36ax-mp 5 . . . . . . 7 ¬ +∞ < -∞
38 breq12 5090 . . . . . . 7 ((𝐵 = +∞ ∧ 𝐴 = -∞) → (𝐵 < 𝐴 ↔ +∞ < -∞))
3937, 38mtbiri 327 . . . . . 6 ((𝐵 = +∞ ∧ 𝐴 = -∞) → ¬ 𝐵 < 𝐴)
4039ancoms 458 . . . . 5 ((𝐴 = -∞ ∧ 𝐵 = +∞) → ¬ 𝐵 < 𝐴)
4140a1d 25 . . . 4 ((𝐴 = -∞ ∧ 𝐵 = +∞) → (𝐴 < 𝐵 → ¬ 𝐵 < 𝐴))
42 xrltnr 13070 . . . . . . 7 (-∞ ∈ ℝ* → ¬ -∞ < -∞)
4335, 42ax-mp 5 . . . . . 6 ¬ -∞ < -∞
44 breq12 5090 . . . . . 6 ((𝐴 = -∞ ∧ 𝐵 = -∞) → (𝐴 < 𝐵 ↔ -∞ < -∞))
4543, 44mtbiri 327 . . . . 5 ((𝐴 = -∞ ∧ 𝐵 = -∞) → ¬ 𝐴 < 𝐵)
4645pm2.21d 121 . . . 4 ((𝐴 = -∞ ∧ 𝐵 = -∞) → (𝐴 < 𝐵 → ¬ 𝐵 < 𝐴))
4734, 41, 463jaodan 1434 . . 3 ((𝐴 = -∞ ∧ (𝐵 ∈ ℝ ∨ 𝐵 = +∞ ∨ 𝐵 = -∞)) → (𝐴 < 𝐵 → ¬ 𝐵 < 𝐴))
4819, 26, 473jaoian 1433 . 2 (((𝐴 ∈ ℝ ∨ 𝐴 = +∞ ∨ 𝐴 = -∞) ∧ (𝐵 ∈ ℝ ∨ 𝐵 = +∞ ∨ 𝐵 = -∞)) → (𝐴 < 𝐵 → ¬ 𝐵 < 𝐴))
491, 2, 48syl2anb 599 1 ((𝐴 ∈ ℝ*𝐵 ∈ ℝ*) → (𝐴 < 𝐵 → ¬ 𝐵 < 𝐴))
Colors of variables: wff setvar class
Syntax hints:  ¬ wn 3  wi 4  wb 206  wa 395  w3o 1086   = wceq 1542  wcel 2114   class class class wbr 5085  cr 11037  +∞cpnf 11176  -∞cmnf 11177  *cxr 11178   < clt 11179
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1912  ax-6 1969  ax-7 2010  ax-8 2116  ax-9 2124  ax-10 2147  ax-11 2163  ax-12 2185  ax-ext 2708  ax-sep 5231  ax-nul 5241  ax-pow 5307  ax-pr 5375  ax-un 7689  ax-cnex 11094  ax-resscn 11095  ax-pre-lttri 11112  ax-pre-lttrn 11113
This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3or 1088  df-3an 1089  df-tru 1545  df-fal 1555  df-ex 1782  df-nf 1786  df-sb 2069  df-mo 2539  df-eu 2569  df-clab 2715  df-cleq 2728  df-clel 2811  df-nfc 2885  df-ne 2933  df-nel 3037  df-ral 3052  df-rex 3062  df-rab 3390  df-v 3431  df-sbc 3729  df-csb 3838  df-dif 3892  df-un 3894  df-in 3896  df-ss 3906  df-nul 4274  df-if 4467  df-pw 4543  df-sn 4568  df-pr 4570  df-op 4574  df-uni 4851  df-br 5086  df-opab 5148  df-mpt 5167  df-id 5526  df-po 5539  df-so 5540  df-xp 5637  df-rel 5638  df-cnv 5639  df-co 5640  df-dm 5641  df-rn 5642  df-res 5643  df-ima 5644  df-iota 6454  df-fun 6500  df-fn 6501  df-f 6502  df-f1 6503  df-fo 6504  df-f1o 6505  df-fv 6506  df-er 8643  df-en 8894  df-dom 8895  df-sdom 8896  df-pnf 11181  df-mnf 11182  df-xr 11183  df-ltxr 11184
This theorem is referenced by:  xrltnsym2  13089  xrlttri  13090  xmullem2  13217  sgnp  15052  iccpartnel  47898
  Copyright terms: Public domain W3C validator