Theorem infsnti 7132

Description: The infimum of a singleton. (Contributed by Jim Kingdon, 19-Dec-2021.)

Hypotheses

Ref	Expression
infsnti.ti	|- ( ( ph /\ ( u e. A /\ v e. A ) ) -> ( u = v <-> ( -. u R v /\ -. v R u ) ) )
infsnti.b	|- ( ph -> B e. A )

Assertion

Ref	Expression
infsnti	|- ( ph -> inf ( { B } , A , R ) = B )

Distinct variable groups:   u, A, v   u, B, v   u, R, v   ph, u, v

Proof of Theorem infsnti

Step	Hyp	Ref	Expression
1		df-inf 7087	. 2 |- inf ( { B } , A , R ) = sup ( { B } , A , `' R )
2		infsnti.ti	. . . 4 |- ( ( ph /\ ( u e. A /\ v e. A ) ) -> ( u = v <-> ( -. u R v /\ -. v R u ) ) )
3	2	cnvti 7121	. . 3 |- ( ( ph /\ ( u e. A /\ v e. A ) ) -> ( u = v <-> ( -. u `' R v /\ -. v `' R u ) ) )
4		infsnti.b	. . 3 |- ( ph -> B e. A )
5	3, 4	supsnti 7107	. 2 |- ( ph -> sup ( { B } , A , `' R ) = B )
6	1, 5	eqtrid 2250	1 |- ( ph -> inf ( { B } , A , R ) = B )

Syntax hints:   -. wn 3   -> wi 4   /\ wa 104   <-> wb 105   = wceq 1373   e. wcel 2176   {csn 3633   class class class wbr 4044   `'ccnv 4674   supcsup 7084  infcinf 7085

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 615  ax-in2 616  ax-io 711  ax-5 1470  ax-7 1471  ax-gen 1472  ax-ie1 1516  ax-ie2 1517  ax-8 1527  ax-10 1528  ax-11 1529  ax-i12 1530  ax-bndl 1532  ax-4 1533  ax-17 1549  ax-i9 1553  ax-ial 1557  ax-i5r 1558  ax-14 2179  ax-ext 2187  ax-sep 4162  ax-pow 4218  ax-pr 4253

This theorem depends on definitions:  df-bi 117  df-3an 983  df-tru 1376  df-fal 1379  df-nf 1484  df-sb 1786  df-eu 2057  df-mo 2058  df-clab 2192  df-cleq 2198  df-clel 2201  df-nfc 2337  df-ral 2489  df-rex 2490  df-reu 2491  df-rmo 2492  df-rab 2493  df-v 2774  df-sbc 2999  df-un 3170  df-in 3172  df-ss 3179  df-pw 3618  df-sn 3639  df-pr 3640  df-op 3642  df-uni 3851  df-br 4045  df-opab 4106  df-cnv 4683  df-iota 5232  df-riota 5899  df-sup 7086  df-inf 7087

This theorem is referenced by: (None)