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Theorem 0npr 7702
Description: The empty set is not a positive real. (Contributed by NM, 15-Nov-1995.)
Assertion
Ref Expression
0npr ¬ ∅ ∈ P

Proof of Theorem 0npr
StepHypRef Expression
1 noel 3498 . . . . . 6 ¬ 𝑥 ∈ ∅
2 1st0 6306 . . . . . . 7 (1st ‘∅) = ∅
32eleq2i 2298 . . . . . 6 (𝑥 ∈ (1st ‘∅) ↔ 𝑥 ∈ ∅)
41, 3mtbir 677 . . . . 5 ¬ 𝑥 ∈ (1st ‘∅)
54nex 1548 . . . 4 ¬ ∃𝑥 𝑥 ∈ (1st ‘∅)
6 rexex 2578 . . . 4 (∃𝑥Q 𝑥 ∈ (1st ‘∅) → ∃𝑥 𝑥 ∈ (1st ‘∅))
75, 6mto 668 . . 3 ¬ ∃𝑥Q 𝑥 ∈ (1st ‘∅)
8 prml 7696 . . 3 (⟨(1st ‘∅), (2nd ‘∅)⟩ ∈ P → ∃𝑥Q 𝑥 ∈ (1st ‘∅))
97, 8mto 668 . 2 ¬ ⟨(1st ‘∅), (2nd ‘∅)⟩ ∈ P
10 prop 7694 . 2 (∅ ∈ P → ⟨(1st ‘∅), (2nd ‘∅)⟩ ∈ P)
119, 10mto 668 1 ¬ ∅ ∈ P
Colors of variables: wff set class
Syntax hints:  ¬ wn 3  wex 1540  wcel 2202  wrex 2511  c0 3494  cop 3672  cfv 5326  1st c1st 6300  2nd c2nd 6301  Qcnq 7499  Pcnp 7510
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 619  ax-in2 620  ax-io 716  ax-5 1495  ax-7 1496  ax-gen 1497  ax-ie1 1541  ax-ie2 1542  ax-8 1552  ax-10 1553  ax-11 1554  ax-i12 1555  ax-bndl 1557  ax-4 1558  ax-17 1574  ax-i9 1578  ax-ial 1582  ax-i5r 1583  ax-13 2204  ax-14 2205  ax-ext 2213  ax-coll 4204  ax-sep 4207  ax-nul 4215  ax-pow 4264  ax-pr 4299  ax-un 4530  ax-iinf 4686
This theorem depends on definitions:  df-bi 117  df-3an 1006  df-tru 1400  df-fal 1403  df-nf 1509  df-sb 1811  df-eu 2082  df-mo 2083  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2363  df-ne 2403  df-ral 2515  df-rex 2516  df-reu 2517  df-rab 2519  df-v 2804  df-sbc 3032  df-csb 3128  df-dif 3202  df-un 3204  df-in 3206  df-ss 3213  df-nul 3495  df-pw 3654  df-sn 3675  df-pr 3676  df-op 3678  df-uni 3894  df-int 3929  df-iun 3972  df-br 4089  df-opab 4151  df-mpt 4152  df-id 4390  df-iom 4689  df-xp 4731  df-rel 4732  df-cnv 4733  df-co 4734  df-dm 4735  df-rn 4736  df-res 4737  df-ima 4738  df-iota 5286  df-fun 5328  df-fn 5329  df-f 5330  df-f1 5331  df-fo 5332  df-f1o 5333  df-fv 5334  df-1st 6302  df-2nd 6303  df-qs 6707  df-ni 7523  df-nqqs 7567  df-inp 7685
This theorem is referenced by: (None)
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