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Theorem 1xr 7930
Description: 1 is an extended real number. (Contributed by Glauco Siliprandi, 2-Jan-2022.)
Assertion
Ref Expression
1xr 1 ∈ ℝ*

Proof of Theorem 1xr
StepHypRef Expression
1 1re 7871 . 2 1 ∈ ℝ
21rexri 7929 1 1 ∈ ℝ*
Colors of variables: wff set class
Syntax hints:  wcel 2128  1c1 7727  *cxr 7905
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 699  ax-5 1427  ax-7 1428  ax-gen 1429  ax-ie1 1473  ax-ie2 1474  ax-8 1484  ax-10 1485  ax-11 1486  ax-i12 1487  ax-bndl 1489  ax-4 1490  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-i5r 1515  ax-ext 2139  ax-1re 7820
This theorem depends on definitions:  df-bi 116  df-tru 1338  df-nf 1441  df-sb 1743  df-clab 2144  df-cleq 2150  df-clel 2153  df-nfc 2288  df-v 2714  df-un 3106  df-in 3108  df-ss 3115  df-xr 7910
This theorem is referenced by:  fprodge1  11529
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