Theorem lt0ne0 8385

Description: A number which is less than zero is not zero. See also lt0ap0 8605 which is similar but for apartness. (Contributed by Stefan O'Rear, 13-Sep-2014.)

Assertion

Ref	Expression
lt0ne0	|- ( ( A e. RR /\ A < 0 ) -> A =/= 0 )

Proof of Theorem lt0ne0

Step	Hyp	Ref	Expression
1		ltne 8042	. 2 |- ( ( A e. RR /\ A < 0 ) -> 0 =/= A )
2	1	necomd 2433	1 |- ( ( A e. RR /\ A < 0 ) -> A =/= 0 )

Syntax hints:   -> wi 4   /\ wa 104   e. wcel 2148   =/= wne 2347   class class class wbr 4004   RRcr 7810   0cc0 7811   < clt 7992

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 614  ax-in2 615  ax-io 709  ax-5 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-10 1505  ax-11 1506  ax-i12 1507  ax-bndl 1509  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-13 2150  ax-14 2151  ax-ext 2159  ax-sep 4122  ax-pow 4175  ax-pr 4210  ax-un 4434  ax-setind 4537  ax-cnex 7902  ax-resscn 7903  ax-pre-ltirr 7923

This theorem depends on definitions:  df-bi 117  df-3an 980  df-tru 1356  df-fal 1359  df-nf 1461  df-sb 1763  df-eu 2029  df-mo 2030  df-clab 2164  df-cleq 2170  df-clel 2173  df-nfc 2308  df-ne 2348  df-nel 2443  df-ral 2460  df-rex 2461  df-rab 2464  df-v 2740  df-dif 3132  df-un 3134  df-in 3136  df-ss 3143  df-pw 3578  df-sn 3599  df-pr 3600  df-op 3602  df-uni 3811  df-br 4005  df-opab 4066  df-xp 4633  df-pnf 7994  df-mnf 7995  df-ltxr 7997

This theorem is referenced by: (None)