Theorem suprubex 8904

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 3156	. 2 |- ( ph -> B e. RR )
4		lttri3 8033	. . . 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 6994	. 2 |- ( ph -> sup ( A , RR , < ) e. RR )
8	5, 6	supubti 6995	. . 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 8074	1 |- ( ph -> B <_ sup ( A , RR , < ) )

Syntax hints:   -. wn 3   -> wi 4   /\ wa 104   <-> wb 105   e. wcel 2148   A.wral 2455   E.wrex 2456   C_ wss 3129   class class class wbr 4002   supcsup 6978   RRcr 7807   < clt 7988   <_ cle 7989

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 4120  ax-pow 4173  ax-pr 4208  ax-un 4432  ax-setind 4535  ax-cnex 7899  ax-resscn 7900  ax-pre-ltirr 7920  ax-pre-apti 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-reu 2462  df-rmo 2463  df-rab 2464  df-v 2739  df-sbc 2963  df-dif 3131  df-un 3133  df-in 3135  df-ss 3142  df-pw 3577  df-sn 3598  df-pr 3599  df-op 3601  df-uni 3810  df-br 4003  df-opab 4064  df-xp 4631  df-cnv 4633  df-iota 5177  df-riota 5828  df-sup 6980  df-pnf 7990  df-mnf 7991  df-xr 7992  df-ltxr 7993  df-le 7994

This theorem is referenced by:  suprzclex  9347