Theorem modgcd 15253

Description: The gcd remains unchanged if one operand is replaced with its remainder modulo the other. (Contributed by Paul Chapman, 31-Mar-2011.)

Assertion

Ref	Expression
modgcd	|- ( ( M e. ZZ /\ N e. NN ) -> ( ( M mod N ) gcd N ) = ( M gcd N ) )

Proof of Theorem modgcd

Step	Hyp	Ref	Expression
1		zre 11381	. . . . . 6 |- ( M e. ZZ -> M e. RR )
2		nnrp 11842	. . . . . 6 |- ( N e. NN -> N e. RR+ )
3		modval 12670	. . . . . 6 |- ( ( M e. RR /\ N e. RR+ ) -> ( M mod N ) = ( M - ( N x. ( |_ ` ( M / N ) ) ) ) )
4	1, 2, 3	syl2an 494	. . . . 5 |- ( ( M e. ZZ /\ N e. NN ) -> ( M mod N ) = ( M - ( N x. ( |_ ` ( M / N ) ) ) ) )
5		zcn 11382	. . . . . . 7 |- ( M e. ZZ -> M e. CC )
6	5	adantr 481	. . . . . 6 |- ( ( M e. ZZ /\ N e. NN ) -> M e. CC )
7		nncn 11028	. . . . . . 7 |- ( N e. NN -> N e. CC )
8	7	adantl 482	. . . . . 6 |- ( ( M e. ZZ /\ N e. NN ) -> N e. CC )
9		nnre 11027	. . . . . . . . . 10 |- ( N e. NN -> N e. RR )
10		nnne0 11053	. . . . . . . . . 10 |- ( N e. NN -> N =/= 0 )
11		redivcl 10744	. . . . . . . . . 10 |- ( ( M e. RR /\ N e. RR /\ N =/= 0 ) -> ( M / N ) e. RR )
12	1, 9, 10, 11	syl3an 1368	. . . . . . . . 9 |- ( ( M e. ZZ /\ N e. NN /\ N e. NN ) -> ( M / N ) e. RR )
13	12	3anidm23 1385	. . . . . . . 8 |- ( ( M e. ZZ /\ N e. NN ) -> ( M / N ) e. RR )
14	13	flcld 12599	. . . . . . 7 |- ( ( M e. ZZ /\ N e. NN ) -> ( |_ ` ( M / N ) ) e. ZZ )
15	14	zcnd 11483	. . . . . 6 |- ( ( M e. ZZ /\ N e. NN ) -> ( |_ ` ( M / N ) ) e. CC )
16		mulneg1 10466	. . . . . . . . . . 11 |- ( ( ( |_ ` ( M / N ) ) e. CC /\ N e. CC ) -> ( -u ( |_ ` ( M / N ) ) x. N ) = -u ( ( |_ ` ( M / N ) ) x. N ) )
17		mulcom 10022	. . . . . . . . . . . 12 |- ( ( ( |_ ` ( M / N ) ) e. CC /\ N e. CC ) -> ( ( |_ ` ( M / N ) ) x. N ) = ( N x. ( |_ ` ( M / N ) ) ) )
18	17	negeqd 10275	. . . . . . . . . . 11 |- ( ( ( |_ ` ( M / N ) ) e. CC /\ N e. CC ) -> -u ( ( |_ ` ( M / N ) ) x. N ) = -u ( N x. ( |_ ` ( M / N ) ) ) )
19	16, 18	eqtrd 2656	. . . . . . . . . 10 |- ( ( ( |_ ` ( M / N ) ) e. CC /\ N e. CC ) -> ( -u ( |_ ` ( M / N ) ) x. N ) = -u ( N x. ( |_ ` ( M / N ) ) ) )
20	19	ancoms 469	. . . . . . . . 9 |- ( ( N e. CC /\ ( |_ ` ( M / N ) ) e. CC ) -> ( -u ( |_ ` ( M / N ) ) x. N ) = -u ( N x. ( |_ ` ( M / N ) ) ) )
21	20	3adant1 1079	. . . . . . . 8 |- ( ( M e. CC /\ N e. CC /\ ( |_ ` ( M / N ) ) e. CC ) -> ( -u ( |_ ` ( M / N ) ) x. N ) = -u ( N x. ( |_ ` ( M / N ) ) ) )
22	21	oveq2d 6666	. . . . . . 7 |- ( ( M e. CC /\ N e. CC /\ ( |_ ` ( M / N ) ) e. CC ) -> ( M + ( -u ( |_ ` ( M / N ) ) x. N ) ) = ( M + -u ( N x. ( |_ ` ( M / N ) ) ) ) )
23		mulcl 10020	. . . . . . . . 9 |- ( ( N e. CC /\ ( |_ ` ( M / N ) ) e. CC ) -> ( N x. ( |_ ` ( M / N ) ) ) e. CC )
24		negsub 10329	. . . . . . . . 9 |- ( ( M e. CC /\ ( N x. ( |_ ` ( M / N ) ) ) e. CC ) -> ( M + -u ( N x. ( |_ ` ( M / N ) ) ) ) = ( M - ( N x. ( |_ ` ( M / N ) ) ) ) )
25	23, 24	sylan2 491	. . . . . . . 8 |- ( ( M e. CC /\ ( N e. CC /\ ( |_ ` ( M / N ) ) e. CC ) ) -> ( M + -u ( N x. ( |_ ` ( M / N ) ) ) ) = ( M - ( N x. ( |_ ` ( M / N ) ) ) ) )
26	25	3impb 1260	. . . . . . 7 |- ( ( M e. CC /\ N e. CC /\ ( |_ ` ( M / N ) ) e. CC ) -> ( M + -u ( N x. ( |_ ` ( M / N ) ) ) ) = ( M - ( N x. ( |_ ` ( M / N ) ) ) ) )
27	22, 26	eqtrd 2656	. . . . . 6 |- ( ( M e. CC /\ N e. CC /\ ( |_ ` ( M / N ) ) e. CC ) -> ( M + ( -u ( |_ ` ( M / N ) ) x. N ) ) = ( M - ( N x. ( |_ ` ( M / N ) ) ) ) )
28	6, 8, 15, 27	syl3anc 1326	. . . . 5 |- ( ( M e. ZZ /\ N e. NN ) -> ( M + ( -u ( |_ ` ( M / N ) ) x. N ) ) = ( M - ( N x. ( |_ ` ( M / N ) ) ) ) )
29	4, 28	eqtr4d 2659	. . . 4 |- ( ( M e. ZZ /\ N e. NN ) -> ( M mod N ) = ( M + ( -u ( |_ ` ( M / N ) ) x. N ) ) )
30	29	oveq2d 6666	. . 3 |- ( ( M e. ZZ /\ N e. NN ) -> ( N gcd ( M mod N ) ) = ( N gcd ( M + ( -u ( |_ ` ( M / N ) ) x. N ) ) ) )
31	14	znegcld 11484	. . . 4 |- ( ( M e. ZZ /\ N e. NN ) -> -u ( |_ ` ( M / N ) ) e. ZZ )
32		nnz 11399	. . . . 5 |- ( N e. NN -> N e. ZZ )
33	32	adantl 482	. . . 4 |- ( ( M e. ZZ /\ N e. NN ) -> N e. ZZ )
34		simpl 473	. . . 4 |- ( ( M e. ZZ /\ N e. NN ) -> M e. ZZ )
35		gcdaddm 15246	. . . 4 |- ( ( -u ( |_ ` ( M / N ) ) e. ZZ /\ N e. ZZ /\ M e. ZZ ) -> ( N gcd M ) = ( N gcd ( M + ( -u ( |_ ` ( M / N ) ) x. N ) ) ) )
36	31, 33, 34, 35	syl3anc 1326	. . 3 |- ( ( M e. ZZ /\ N e. NN ) -> ( N gcd M ) = ( N gcd ( M + ( -u ( |_ ` ( M / N ) ) x. N ) ) ) )
37	30, 36	eqtr4d 2659	. 2 |- ( ( M e. ZZ /\ N e. NN ) -> ( N gcd ( M mod N ) ) = ( N gcd M ) )
38		zmodcl 12690	. . . 4 |- ( ( M e. ZZ /\ N e. NN ) -> ( M mod N ) e. NN0 )
39	38	nn0zd 11480	. . 3 |- ( ( M e. ZZ /\ N e. NN ) -> ( M mod N ) e. ZZ )
40		gcdcom 15235	. . 3 |- ( ( N e. ZZ /\ ( M mod N ) e. ZZ ) -> ( N gcd ( M mod N ) ) = ( ( M mod N ) gcd N ) )
41	33, 39, 40	syl2anc 693	. 2 |- ( ( M e. ZZ /\ N e. NN ) -> ( N gcd ( M mod N ) ) = ( ( M mod N ) gcd N ) )
42		gcdcom 15235	. . 3 |- ( ( N e. ZZ /\ M e. ZZ ) -> ( N gcd M ) = ( M gcd N ) )
43	33, 34, 42	syl2anc 693	. 2 |- ( ( M e. ZZ /\ N e. NN ) -> ( N gcd M ) = ( M gcd N ) )
44	37, 41, 43	3eqtr3d 2664	1 |- ( ( M e. ZZ /\ N e. NN ) -> ( ( M mod N ) gcd N ) = ( M gcd N ) )

Syntax hints:   -> wi 4   /\ wa 384   /\ w3a 1037   = wceq 1483   e. wcel 1990   =/= wne 2794   ` cfv 5888  (class class class)co 6650   CCcc 9934   RRcr 9935   0cc0 9936   + caddc 9939   x. cmul 9941   - cmin 10266   -ucneg 10267   / cdiv 10684   NNcn 11020   ZZcz 11377   RR+crp 11832   |_cfl 12591   mod cmo 12668   gcd cgcd 15216

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-8 1992  ax-9 1999  ax-10 2019  ax-11 2034  ax-12 2047  ax-13 2246  ax-ext 2602  ax-sep 4781  ax-nul 4789  ax-pow 4843  ax-pr 4906  ax-un 6949  ax-cnex 9992  ax-resscn 9993  ax-1cn 9994  ax-icn 9995  ax-addcl 9996  ax-addrcl 9997  ax-mulcl 9998  ax-mulrcl 9999  ax-mulcom 10000  ax-addass 10001  ax-mulass 10002  ax-distr 10003  ax-i2m1 10004  ax-1ne0 10005  ax-1rid 10006  ax-rnegex 10007  ax-rrecex 10008  ax-cnre 10009  ax-pre-lttri 10010  ax-pre-lttrn 10011  ax-pre-ltadd 10012  ax-pre-mulgt0 10013  ax-pre-sup 10014

This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3or 1038  df-3an 1039  df-tru 1486  df-ex 1705  df-nf 1710  df-sb 1881  df-eu 2474  df-mo 2475  df-clab 2609  df-cleq 2615  df-clel 2618  df-nfc 2753  df-ne 2795  df-nel 2898  df-ral 2917  df-rex 2918  df-reu 2919  df-rmo 2920  df-rab 2921  df-v 3202  df-sbc 3436  df-csb 3534  df-dif 3577  df-un 3579  df-in 3581  df-ss 3588  df-pss 3590  df-nul 3916  df-if 4087  df-pw 4160  df-sn 4178  df-pr 4180  df-tp 4182  df-op 4184  df-uni 4437  df-iun 4522  df-br 4654  df-opab 4713  df-mpt 4730  df-tr 4753  df-id 5024  df-eprel 5029  df-po 5035  df-so 5036  df-fr 5073  df-we 5075  df-xp 5120  df-rel 5121  df-cnv 5122  df-co 5123  df-dm 5124  df-rn 5125  df-res 5126  df-ima 5127  df-pred 5680  df-ord 5726  df-on 5727  df-lim 5728  df-suc 5729  df-iota 5851  df-fun 5890  df-fn 5891  df-f 5892  df-f1 5893  df-fo 5894  df-f1o 5895  df-fv 5896  df-riota 6611  df-ov 6653  df-oprab 6654  df-mpt2 6655  df-om 7066  df-2nd 7169  df-wrecs 7407  df-recs 7468  df-rdg 7506  df-er 7742  df-en 7956  df-dom 7957  df-sdom 7958  df-sup 8348  df-inf 8349  df-pnf 10076  df-mnf 10077  df-xr 10078  df-ltxr 10079  df-le 10080  df-sub 10268  df-neg 10269  df-div 10685  df-nn 11021  df-2 11079  df-3 11080  df-n0 11293  df-z 11378  df-uz 11688  df-rp 11833  df-fl 12593  df-mod 12669  df-seq 12802  df-exp 12861  df-cj 13839  df-re 13840  df-im 13841  df-sqrt 13975  df-abs 13976  df-dvds 14984  df-gcd 15217

This theorem is referenced by:  eucalginv  15297  phimullem  15484  eulerthlem1  15486  pockthlem  15609  gcdmodi  15778  proththd  41531