Theorem lt0ne0d 8789

Description: Something less than zero is not zero. Deduction form. See also lt0ap0d 8925 which is similar but for apartness. (Contributed by David Moews, 28-Feb-2017.)

Hypothesis

Ref	Expression
lt0ne0d.1	|- ( ph -> A < 0 )

Assertion

Ref	Expression
lt0ne0d	|- ( ph -> A =/= 0 )

Proof of Theorem lt0ne0d

Step	Hyp	Ref	Expression
1		lt0ne0d.1	. 2 |- ( ph -> A < 0 )
2		0re 8276	. . . . 5 |- 0 e. RR
3	2	ltnri 8368	. . . 4 |- -. 0 < 0
4		breq1 4114	. . . 4 |- ( A = 0 -> ( A < 0 <-> 0 < 0 ) )
5	3, 4	mtbiri 682	. . 3 |- ( A = 0 -> -. A < 0 )
6	5	necon2ai 2468	. 2 |- ( A < 0 -> A =/= 0 )
7	1, 6	syl 14	1 |- ( ph -> A =/= 0 )

Syntax hints:   -> wi 4   = wceq 1398   =/= wne 2414   class class class wbr 4111   0cc0 8129   < clt 8310

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 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-13 2207  ax-14 2208  ax-ext 2216  ax-sep 4230  ax-pow 4289  ax-pr 4324  ax-un 4556  ax-setind 4661  ax-cnex 8220  ax-resscn 8221  ax-1re 8223  ax-addrcl 8226  ax-rnegex 8238  ax-pre-ltirr 8241

This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-fal 1404  df-nf 1510  df-sb 1812  df-eu 2085  df-mo 2086  df-clab 2221  df-cleq 2227  df-clel 2230  df-nfc 2375  df-ne 2415  df-nel 2510  df-ral 2527  df-rex 2528  df-rab 2531  df-v 2817  df-dif 3215  df-un 3217  df-in 3219  df-ss 3226  df-pw 3673  df-sn 3697  df-pr 3698  df-op 3700  df-uni 3917  df-br 4112  df-opab 4174  df-xp 4757  df-pnf 8312  df-mnf 8313  df-ltxr 8315

This theorem is referenced by:  divalglemeuneg  12613