Theorem elioo2 10260

Description: Membership in an open interval of extended reals. (Contributed by NM, 6-Feb-2007.)

Assertion

Ref	Expression
elioo2	|- ( ( A e. RR* /\ B e. RR* ) -> ( C e. ( A (,) B ) <-> ( C e. RR /\ A < C /\ C < B ) ) )

Proof of Theorem elioo2

Dummy variable x is distinct from all other variables.

Step	Hyp	Ref	Expression
1		iooval2 10254	. . 3 |- ( ( A e. RR* /\ B e. RR* ) -> ( A (,) B ) = { x e. RR | ( A < x /\ x < B ) } )
2	1	eleq2d 2304	. 2 |- ( ( A e. RR* /\ B e. RR* ) -> ( C e. ( A (,) B ) <-> C e. { x e. RR | ( A < x /\ x < B ) } ) )
3		breq2 4115	. . . . 5 |- ( x = C -> ( A < x <-> A < C ) )
4		breq1 4114	. . . . 5 |- ( x = C -> ( x < B <-> C < B ) )
5	3, 4	anbi12d 473	. . . 4 |- ( x = C -> ( ( A < x /\ x < B ) <-> ( A < C /\ C < B ) ) )
6	5	elrab 2975	. . 3 |- ( C e. { x e. RR | ( A < x /\ x < B ) } <-> ( C e. RR /\ ( A < C /\ C < B ) ) )
7		3anass 1009	. . 3 |- ( ( C e. RR /\ A < C /\ C < B ) <-> ( C e. RR /\ ( A < C /\ C < B ) ) )
8	6, 7	bitr4i 187	. 2 |- ( C e. { x e. RR | ( A < x /\ x < B ) } <-> ( C e. RR /\ A < C /\ C < B ) )
9	2, 8	bitrdi 196	1 |- ( ( A e. RR* /\ B e. RR* ) -> ( C e. ( A (,) B ) <-> ( C e. RR /\ A < C /\ C < B ) ) )

Syntax hints:   -> wi 4   /\ wa 104   <-> wb 105   /\ w3a 1005   = wceq 1398   e. wcel 2205   {crab 2526   class class class wbr 4111  (class class class)co 6052   RRcr 8131   RR*cxr 8312   < clt 8313   (,)cioo 10227

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 8223  ax-resscn 8224  ax-pre-ltirr 8244  ax-pre-ltwlin 8245  ax-pre-lttrn 8246

This theorem depends on definitions:  df-bi 117  df-3or 1006  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-sbc 3045  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-id 4416  df-po 4419  df-iso 4420  df-xp 4757  df-rel 4758  df-cnv 4759  df-co 4760  df-dm 4761  df-iota 5314  df-fun 5356  df-fv 5362  df-ov 6055  df-oprab 6056  df-mpo 6057  df-pnf 8315  df-mnf 8316  df-xr 8317  df-ltxr 8318  df-le 8319  df-ioo 10231

This theorem is referenced by:  eliooord  10267  elioopnf  10306  elioomnf  10307  dfrp2  10630  bl2ioo  15464  dedekindicc  15547  reeff1oleme  15686  reeff1o  15687  sin0pilem2  15696  pilem3  15697  sincosq1sgn  15740  sincosq2sgn  15741  sincosq3sgn  15742  sincosq4sgn  15743  sinq12gt0  15744  cosq14gt0  15746  cosq23lt0  15747  coseq0q4123  15748  coseq00topi  15749  coseq0negpitopi  15750  sincos6thpi  15756  cosordlem  15763  cos02pilt1  15765  cos0pilt1  15766  ioocosf1o  15768  iooref1o  16867  taupi  16908