Theorem zmulcl 10691

Description: Closure of multiplication of integers. (Contributed by NM, 30-Jul-2004.)

Assertion

Ref	Expression
zmulcl	|- ( ( M e. ZZ /\ N e. ZZ ) -> ( M x. N ) e. ZZ )

Proof of Theorem zmulcl

Step	Hyp	Ref	Expression
1		elznn0 10659	. 2 |- ( M e. ZZ <-> ( M e. RR /\ ( M e. NN0 \/ -u M e. NN0 ) ) )
2		elznn0 10659	. 2 |- ( N e. ZZ <-> ( N e. RR /\ ( N e. NN0 \/ -u N e. NN0 ) ) )
3		nn0mulcl 10614	. . . . . . . . 9 |- ( ( M e. NN0 /\ N e. NN0 ) -> ( M x. N ) e. NN0 )
4	3	orcd 392	. . . . . . . 8 |- ( ( M e. NN0 /\ N e. NN0 ) -> ( ( M x. N ) e. NN0 \/ -u ( M x. N ) e. NN0 ) )
5	4	a1i 11	. . . . . . 7 |- ( ( M e. RR /\ N e. RR ) -> ( ( M e. NN0 /\ N e. NN0 ) -> ( ( M x. N ) e. NN0 \/ -u ( M x. N ) e. NN0 ) ) )
6		remulcl 9365	. . . . . . 7 |- ( ( M e. RR /\ N e. RR ) -> ( M x. N ) e. RR )
7	5, 6	jctild 543	. . . . . 6 |- ( ( M e. RR /\ N e. RR ) -> ( ( M e. NN0 /\ N e. NN0 ) -> ( ( M x. N ) e. RR /\ ( ( M x. N ) e. NN0 \/ -u ( M x. N ) e. NN0 ) ) ) )
8		nn0mulcl 10614	. . . . . . . . 9 |- ( ( -u M e. NN0 /\ N e. NN0 ) -> ( -u M x. N ) e. NN0 )
9		recn 9370	. . . . . . . . . . 11 |- ( M e. RR -> M e. CC )
10		recn 9370	. . . . . . . . . . 11 |- ( N e. RR -> N e. CC )
11		mulneg1 9779	. . . . . . . . . . 11 |- ( ( M e. CC /\ N e. CC ) -> ( -u M x. N ) = -u ( M x. N ) )
12	9, 10, 11	syl2an 477	. . . . . . . . . 10 |- ( ( M e. RR /\ N e. RR ) -> ( -u M x. N ) = -u ( M x. N ) )
13	12	eleq1d 2507	. . . . . . . . 9 |- ( ( M e. RR /\ N e. RR ) -> ( ( -u M x. N ) e. NN0 <-> -u ( M x. N ) e. NN0 ) )
14	8, 13	syl5ib 219	. . . . . . . 8 |- ( ( M e. RR /\ N e. RR ) -> ( ( -u M e. NN0 /\ N e. NN0 ) -> -u ( M x. N ) e. NN0 ) )
15		olc 384	. . . . . . . 8 |- ( -u ( M x. N ) e. NN0 -> ( ( M x. N ) e. NN0 \/ -u ( M x. N ) e. NN0 ) )
16	14, 15	syl6 33	. . . . . . 7 |- ( ( M e. RR /\ N e. RR ) -> ( ( -u M e. NN0 /\ N e. NN0 ) -> ( ( M x. N ) e. NN0 \/ -u ( M x. N ) e. NN0 ) ) )
17	16, 6	jctild 543	. . . . . 6 |- ( ( M e. RR /\ N e. RR ) -> ( ( -u M e. NN0 /\ N e. NN0 ) -> ( ( M x. N ) e. RR /\ ( ( M x. N ) e. NN0 \/ -u ( M x. N ) e. NN0 ) ) ) )
18		nn0mulcl 10614	. . . . . . . . 9 |- ( ( M e. NN0 /\ -u N e. NN0 ) -> ( M x. -u N ) e. NN0 )
19		mulneg2 9780	. . . . . . . . . . 11 |- ( ( M e. CC /\ N e. CC ) -> ( M x. -u N ) = -u ( M x. N ) )
20	9, 10, 19	syl2an 477	. . . . . . . . . 10 |- ( ( M e. RR /\ N e. RR ) -> ( M x. -u N ) = -u ( M x. N ) )
21	20	eleq1d 2507	. . . . . . . . 9 |- ( ( M e. RR /\ N e. RR ) -> ( ( M x. -u N ) e. NN0 <-> -u ( M x. N ) e. NN0 ) )
22	18, 21	syl5ib 219	. . . . . . . 8 |- ( ( M e. RR /\ N e. RR ) -> ( ( M e. NN0 /\ -u N e. NN0 ) -> -u ( M x. N ) e. NN0 ) )
23	22, 15	syl6 33	. . . . . . 7 |- ( ( M e. RR /\ N e. RR ) -> ( ( M e. NN0 /\ -u N e. NN0 ) -> ( ( M x. N ) e. NN0 \/ -u ( M x. N ) e. NN0 ) ) )
24	23, 6	jctild 543	. . . . . 6 |- ( ( M e. RR /\ N e. RR ) -> ( ( M e. NN0 /\ -u N e. NN0 ) -> ( ( M x. N ) e. RR /\ ( ( M x. N ) e. NN0 \/ -u ( M x. N ) e. NN0 ) ) ) )
25		nn0mulcl 10614	. . . . . . . . 9 |- ( ( -u M e. NN0 /\ -u N e. NN0 ) -> ( -u M x. -u N ) e. NN0 )
26		mul2neg 9782	. . . . . . . . . . 11 |- ( ( M e. CC /\ N e. CC ) -> ( -u M x. -u N ) = ( M x. N ) )
27	9, 10, 26	syl2an 477	. . . . . . . . . 10 |- ( ( M e. RR /\ N e. RR ) -> ( -u M x. -u N ) = ( M x. N ) )
28	27	eleq1d 2507	. . . . . . . . 9 |- ( ( M e. RR /\ N e. RR ) -> ( ( -u M x. -u N ) e. NN0 <-> ( M x. N ) e. NN0 ) )
29	25, 28	syl5ib 219	. . . . . . . 8 |- ( ( M e. RR /\ N e. RR ) -> ( ( -u M e. NN0 /\ -u N e. NN0 ) -> ( M x. N ) e. NN0 ) )
30		orc 385	. . . . . . . 8 |- ( ( M x. N ) e. NN0 -> ( ( M x. N ) e. NN0 \/ -u ( M x. N ) e. NN0 ) )
31	29, 30	syl6 33	. . . . . . 7 |- ( ( M e. RR /\ N e. RR ) -> ( ( -u M e. NN0 /\ -u N e. NN0 ) -> ( ( M x. N ) e. NN0 \/ -u ( M x. N ) e. NN0 ) ) )
32	31, 6	jctild 543	. . . . . 6 |- ( ( M e. RR /\ N e. RR ) -> ( ( -u M e. NN0 /\ -u N e. NN0 ) -> ( ( M x. N ) e. RR /\ ( ( M x. N ) e. NN0 \/ -u ( M x. N ) e. NN0 ) ) ) )
33	7, 17, 24, 32	ccased 938	. . . . 5 |- ( ( M e. RR /\ N e. RR ) -> ( ( ( M e. NN0 \/ -u M e. NN0 ) /\ ( N e. NN0 \/ -u N e. NN0 ) ) -> ( ( M x. N ) e. RR /\ ( ( M x. N ) e. NN0 \/ -u ( M x. N ) e. NN0 ) ) ) )
34		elznn0 10659	. . . . 5 |- ( ( M x. N ) e. ZZ <-> ( ( M x. N ) e. RR /\ ( ( M x. N ) e. NN0 \/ -u ( M x. N ) e. NN0 ) ) )
35	33, 34	syl6ibr 227	. . . 4 |- ( ( M e. RR /\ N e. RR ) -> ( ( ( M e. NN0 \/ -u M e. NN0 ) /\ ( N e. NN0 \/ -u N e. NN0 ) ) -> ( M x. N ) e. ZZ ) )
36	35	imp 429	. . 3 |- ( ( ( M e. RR /\ N e. RR ) /\ ( ( M e. NN0 \/ -u M e. NN0 ) /\ ( N e. NN0 \/ -u N e. NN0 ) ) ) -> ( M x. N ) e. ZZ )
37	36	an4s 822	. 2 |- ( ( ( M e. RR /\ ( M e. NN0 \/ -u M e. NN0 ) ) /\ ( N e. RR /\ ( N e. NN0 \/ -u N e. NN0 ) ) ) -> ( M x. N ) e. ZZ )
38	1, 2, 37	syl2anb 479	1 |- ( ( M e. ZZ /\ N e. ZZ ) -> ( M x. N ) e. ZZ )

Syntax hints:   -> wi 4   \/ wo 368   /\ wa 369   = wceq 1369   e. wcel 1756  (class class class)co 6089   CCcc 9278   RRcr 9279   x. cmul 9285   -ucneg 9594   NN0cn0 10577   ZZcz 10644

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1591  ax-4 1602  ax-5 1670  ax-6 1708  ax-7 1728  ax-8 1758  ax-9 1760  ax-10 1775  ax-11 1780  ax-12 1792  ax-13 1943  ax-ext 2422  ax-sep 4411  ax-nul 4419  ax-pow 4468  ax-pr 4529  ax-un 6370  ax-resscn 9337  ax-1cn 9338  ax-icn 9339  ax-addcl 9340  ax-addrcl 9341  ax-mulcl 9342  ax-mulrcl 9343  ax-mulcom 9344  ax-addass 9345  ax-mulass 9346  ax-distr 9347  ax-i2m1 9348  ax-1ne0 9349  ax-1rid 9350  ax-rnegex 9351  ax-rrecex 9352  ax-cnre 9353  ax-pre-lttri 9354  ax-pre-lttrn 9355  ax-pre-ltadd 9356

This theorem depends on definitions:  df-bi 185  df-or 370  df-an 371  df-3or 966  df-3an 967  df-tru 1372  df-ex 1587  df-nf 1590  df-sb 1701  df-eu 2257  df-mo 2258  df-clab 2428  df-cleq 2434  df-clel 2437  df-nfc 2566  df-ne 2606  df-nel 2607  df-ral 2718  df-rex 2719  df-reu 2720  df-rab 2722  df-v 2972  df-sbc 3185  df-csb 3287  df-dif 3329  df-un 3331  df-in 3333  df-ss 3340  df-pss 3342  df-nul 3636  df-if 3790  df-pw 3860  df-sn 3876  df-pr 3878  df-tp 3880  df-op 3882  df-uni 4090  df-iun 4171  df-br 4291  df-opab 4349  df-mpt 4350  df-tr 4384  df-eprel 4630  df-id 4634  df-po 4639  df-so 4640  df-fr 4677  df-we 4679  df-ord 4720  df-on 4721  df-lim 4722  df-suc 4723  df-xp 4844  df-rel 4845  df-cnv 4846  df-co 4847  df-dm 4848  df-rn 4849  df-res 4850  df-ima 4851  df-iota 5379  df-fun 5418  df-fn 5419  df-f 5420  df-f1 5421  df-fo 5422  df-f1o 5423  df-fv 5424  df-riota 6050  df-ov 6092  df-oprab 6093  df-mpt2 6094  df-om 6475  df-recs 6830  df-rdg 6864  df-er 7099  df-en 7309  df-dom 7310  df-sdom 7311  df-pnf 9418  df-mnf 9419  df-ltxr 9421  df-sub 9595  df-neg 9596  df-nn 10321  df-n0 10578  df-z 10645

This theorem is referenced by:  zdivmul  10712  msqznn  10721  zmulcld  10751  uz2mulcl  10930  qaddcl  10967  qmulcl  10969  qreccl  10971  fzctr  11527  flmulnn0  11670  zexpcl  11878  iexpcyc  11968  zesq  11985  cshweqrep  12453  dvdsmul1  13552  dvdsmul2  13553  muldvds1  13555  muldvds2  13556  dvdscmul  13557  dvdsmulc  13558  dvdscmulr  13559  dvdsmulcr  13560  dvds2ln  13561  dvdstr  13564  dvdsmultr1  13565  dvdsmultr2  13566  oexpneg  13593  divalglem0  13595  divalglem2  13597  divalglem4  13598  divalglem8  13602  divalgb  13606  divalgmod  13608  ndvdsi  13612  gcdaddmlem  13710  absmulgcd  13729  gcdmultiple  13732  gcdmultiplez  13733  dvdsmulgcd  13736  rpmulgcd  13737  coprmdvds  13786  rpmul  13807  eulerthlem2  13855  modprminv  13868  modprminveq  13869  modprm0  13871  pythagtriplem4  13884  pcpremul  13908  pcmul  13916  gzmulcl  13997  pgpfac1lem2  16574  zsubrg  17864  dvdsrzring  17899  dvdsrz  17900  mulgrhm  17924  mulgrhmOLD  17927  domnchr  17961  znfld  17991  znunit  17994  mbfi1fseqlem5  21195  dvexp3  21448  basellem2  22417  basellem5  22420  dvdsflf1o  22525  chtub  22549  bposlem1  22621  bposlem5  22625  bposlem6  22626  lgslem3  22635  lgsval4a  22655  lgsneg  22656  lgsdir2  22665  lgsdchr  22685  lgseisenlem1  22686  lgseisenlem2  22687  lgseisenlem3  22688  lgsquadlem1  22691  lgsquad2lem2  22696  chebbnd1lem1  22716  chebbnd1lem3  22718  gxnn0mul  23762  fprodzcl  27465  zrisefaccl  27521  zfallfaccl  27522  fzmul  28633  mzpclall  29060  mzpindd  29079  acongrep  29320  acongeq  29323  jm2.18  29334  jm2.21  29340  jm2.26a  29346  jm2.26  29348  jm2.16nn0  29350  jm2.27a  29351  jm2.27c  29353  jm3.1lem3  29365  zlmodzxzequa  31035  zlmodzxzequap  31038