Theorem suprubex 9121

Description: A member of a nonempty bounded set of reals is less than or equal to the set's upper bound. (Contributed by Jim Kingdon, 18-Jan-2022.)

Hypotheses

Ref	Expression
suprubex.ex	|- ( ph -> E. x e. RR ( A. y e. A -. x < y /\ A. y e. RR ( y < x -> E. z e. A y < z ) ) )
suprubex.ss	|- ( ph -> A C_ RR )
suprubex.b	|- ( ph -> B e. A )

Assertion

Ref	Expression
suprubex	|- ( ph -> B <_ sup ( A , RR , < ) )

Distinct variable groups:   x, A, y, z   ph, x

Allowed substitution hints:   ph( y, z)   B( x, y, z)

Proof of Theorem suprubex

Dummy variables f g are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		suprubex.ss	. . 3 |- ( ph -> A C_ RR )
2		suprubex.b	. . 3 |- ( ph -> B e. A )
3	1, 2	sseldd 3226	. 2 |- ( ph -> B e. RR )
4		lttri3 8249	. . . 4 |- ( ( f e. RR /\ g e. RR ) -> ( f = g <-> ( -. f < g /\ -. g < f ) ) )
5	4	adantl 277	. . 3 |- ( ( ph /\ ( f e. RR /\ g e. RR ) ) -> ( f = g <-> ( -. f < g /\ -. g < f ) ) )
6		suprubex.ex	. . 3 |- ( ph -> E. x e. RR ( A. y e. A -. x < y /\ A. y e. RR ( y < x -> E. z e. A y < z ) ) )
7	5, 6	supclti 7188	. 2 |- ( ph -> sup ( A , RR , < ) e. RR )
8	5, 6	supubti 7189	. . 3 |- ( ph -> ( B e. A -> -. sup ( A , RR , < ) < B ) )
9	2, 8	mpd 13	. 2 |- ( ph -> -. sup ( A , RR , < ) < B )
10	3, 7, 9	nltled 8290	1 |- ( ph -> B <_ sup ( A , RR , < ) )

Syntax hints:   -. wn 3   -> wi 4   /\ wa 104   <-> wb 105   e. wcel 2200   A.wral 2508   E.wrex 2509   C_ wss 3198   class class class wbr 4086   supcsup 7172   RRcr 8021   < clt 8204   <_ cle 8205

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 617  ax-in2 618  ax-io 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-13 2202  ax-14 2203  ax-ext 2211  ax-sep 4205  ax-pow 4262  ax-pr 4297  ax-un 4528  ax-setind 4633  ax-cnex 8113  ax-resscn 8114  ax-pre-ltirr 8134  ax-pre-apti 8137

This theorem depends on definitions:  df-bi 117  df-3an 1004  df-tru 1398  df-fal 1401  df-nf 1507  df-sb 1809  df-eu 2080  df-mo 2081  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-ne 2401  df-nel 2496  df-ral 2513  df-rex 2514  df-reu 2515  df-rmo 2516  df-rab 2517  df-v 2802  df-sbc 3030  df-dif 3200  df-un 3202  df-in 3204  df-ss 3211  df-pw 3652  df-sn 3673  df-pr 3674  df-op 3676  df-uni 3892  df-br 4087  df-opab 4149  df-xp 4729  df-cnv 4731  df-iota 5284  df-riota 5966  df-sup 7174  df-pnf 8206  df-mnf 8207  df-xr 8208  df-ltxr 8209  df-le 8210

This theorem is referenced by:  suprzclex  9568