Theorem uzin2 10944

Description: The upper integers are closed under intersection. (Contributed by Mario Carneiro, 24-Dec-2013.)

Assertion

Ref	Expression
uzin2	|- ( ( A e. ran ZZ>= /\ B e. ran ZZ>= ) -> ( A i^i B ) e. ran ZZ>= )

Proof of Theorem uzin2

Dummy variables x y are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		uzf 9483	. . . 4 |- ZZ>= : ZZ --> ~P ZZ
2		ffn 5345	. . . 4 |- ( ZZ>= : ZZ --> ~P ZZ -> ZZ>= Fn ZZ )
3	1, 2	ax-mp 5	. . 3 |- ZZ>= Fn ZZ
4		fvelrnb 5542	. . 3 |- ( ZZ>= Fn ZZ -> ( A e. ran ZZ>= <-> E. x e. ZZ ( ZZ>= ` x ) = A ) )
5	3, 4	ax-mp 5	. 2 |- ( A e. ran ZZ>= <-> E. x e. ZZ ( ZZ>= ` x ) = A )
6		fvelrnb 5542	. . 3 |- ( ZZ>= Fn ZZ -> ( B e. ran ZZ>= <-> E. y e. ZZ ( ZZ>= ` y ) = B ) )
7	3, 6	ax-mp 5	. 2 |- ( B e. ran ZZ>= <-> E. y e. ZZ ( ZZ>= ` y ) = B )
8		ineq1 3321	. . 3 |- ( ( ZZ>= ` x ) = A -> ( ( ZZ>= ` x ) i^i ( ZZ>= ` y ) ) = ( A i^i ( ZZ>= ` y ) ) )
9	8	eleq1d 2239	. 2 |- ( ( ZZ>= ` x ) = A -> ( ( ( ZZ>= ` x ) i^i ( ZZ>= ` y ) ) e. ran ZZ>= <-> ( A i^i ( ZZ>= ` y ) ) e. ran ZZ>= ) )
10		ineq2 3322	. . 3 |- ( ( ZZ>= ` y ) = B -> ( A i^i ( ZZ>= ` y ) ) = ( A i^i B ) )
11	10	eleq1d 2239	. 2 |- ( ( ZZ>= ` y ) = B -> ( ( A i^i ( ZZ>= ` y ) ) e. ran ZZ>= <-> ( A i^i B ) e. ran ZZ>= ) )
12		uzin 9512	. . 3 |- ( ( x e. ZZ /\ y e. ZZ ) -> ( ( ZZ>= ` x ) i^i ( ZZ>= ` y ) ) = ( ZZ>= ` if ( x <_ y , y , x ) ) )
13		simpr 109	. . . . 5 |- ( ( x e. ZZ /\ y e. ZZ ) -> y e. ZZ )
14		simpl 108	. . . . 5 |- ( ( x e. ZZ /\ y e. ZZ ) -> x e. ZZ )
15		zdcle 9281	. . . . 5 |- ( ( x e. ZZ /\ y e. ZZ ) -> DECID x <_ y )
16	13, 14, 15	ifcldcd 3560	. . . 4 |- ( ( x e. ZZ /\ y e. ZZ ) -> if ( x <_ y , y , x ) e. ZZ )
17		fnfvelrn 5626	. . . 4 |- ( ( ZZ>= Fn ZZ /\ if ( x <_ y , y , x ) e. ZZ ) -> ( ZZ>= ` if ( x <_ y , y , x ) ) e. ran ZZ>= )
18	3, 16, 17	sylancr 412	. . 3 |- ( ( x e. ZZ /\ y e. ZZ ) -> ( ZZ>= ` if ( x <_ y , y , x ) ) e. ran ZZ>= )
19	12, 18	eqeltrd 2247	. 2 |- ( ( x e. ZZ /\ y e. ZZ ) -> ( ( ZZ>= ` x ) i^i ( ZZ>= ` y ) ) e. ran ZZ>= )
20	5, 7, 9, 11, 19	2gencl 2763	1 |- ( ( A e. ran ZZ>= /\ B e. ran ZZ>= ) -> ( A i^i B ) e. ran ZZ>= )

Syntax hints:   -> wi 4   /\ wa 103   <-> wb 104   = wceq 1348   e. wcel 2141   E.wrex 2449   i^i cin 3120   ifcif 3525   ~Pcpw 3564   class class class wbr 3987   ran crn 4610   Fn wfn 5191   -->wf 5192   ` cfv 5196   <_ cle 7948   ZZcz 9205   ZZ>=cuz 9480

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 609  ax-in2 610  ax-io 704  ax-5 1440  ax-7 1441  ax-gen 1442  ax-ie1 1486  ax-ie2 1487  ax-8 1497  ax-10 1498  ax-11 1499  ax-i12 1500  ax-bndl 1502  ax-4 1503  ax-17 1519  ax-i9 1523  ax-ial 1527  ax-i5r 1528  ax-13 2143  ax-14 2144  ax-ext 2152  ax-sep 4105  ax-pow 4158  ax-pr 4192  ax-un 4416  ax-setind 4519  ax-cnex 7858  ax-resscn 7859  ax-1cn 7860  ax-1re 7861  ax-icn 7862  ax-addcl 7863  ax-addrcl 7864  ax-mulcl 7865  ax-addcom 7867  ax-addass 7869  ax-distr 7871  ax-i2m1 7872  ax-0lt1 7873  ax-0id 7875  ax-rnegex 7876  ax-cnre 7878  ax-pre-ltirr 7879  ax-pre-ltwlin 7880  ax-pre-lttrn 7881  ax-pre-apti 7882  ax-pre-ltadd 7883

This theorem depends on definitions:  df-bi 116  df-dc 830  df-3or 974  df-3an 975  df-tru 1351  df-fal 1354  df-nf 1454  df-sb 1756  df-eu 2022  df-mo 2023  df-clab 2157  df-cleq 2163  df-clel 2166  df-nfc 2301  df-ne 2341  df-nel 2436  df-ral 2453  df-rex 2454  df-reu 2455  df-rab 2457  df-v 2732  df-sbc 2956  df-dif 3123  df-un 3125  df-in 3127  df-ss 3134  df-if 3526  df-pw 3566  df-sn 3587  df-pr 3588  df-op 3590  df-uni 3795  df-int 3830  df-br 3988  df-opab 4049  df-mpt 4050  df-id 4276  df-xp 4615  df-rel 4616  df-cnv 4617  df-co 4618  df-dm 4619  df-rn 4620  df-res 4621  df-ima 4622  df-iota 5158  df-fun 5198  df-fn 5199  df-f 5200  df-fv 5204  df-riota 5807  df-ov 5854  df-oprab 5855  df-mpo 5856  df-pnf 7949  df-mnf 7950  df-xr 7951  df-ltxr 7952  df-le 7953  df-sub 8085  df-neg 8086  df-inn 8872  df-n0 9129  df-z 9206  df-uz 9481

This theorem is referenced by:  rexanuz  10945