Metamath Proof Explorer


Theorem odmod

Description: Reduce the argument of a group multiple by modding out the order of the element. (Contributed by Mario Carneiro, 14-Jan-2015) (Revised by Mario Carneiro, 6-Sep-2015)

Ref Expression
Hypotheses odcl.1 X = Base G
odcl.2 O = od G
odid.3 · ˙ = G
odid.4 0 ˙ = 0 G
Assertion odmod G Grp A X N O A N mod O A · ˙ A = N · ˙ A

Proof

Step Hyp Ref Expression
1 odcl.1 X = Base G
2 odcl.2 O = od G
3 odid.3 · ˙ = G
4 odid.4 0 ˙ = 0 G
5 simpl3 G Grp A X N O A N
6 5 zred G Grp A X N O A N
7 simpr G Grp A X N O A O A
8 7 nnrpd G Grp A X N O A O A +
9 modval N O A + N mod O A = N O A N O A
10 6 8 9 syl2anc G Grp A X N O A N mod O A = N O A N O A
11 10 oveq1d G Grp A X N O A N mod O A · ˙ A = N O A N O A · ˙ A
12 simpl1 G Grp A X N O A G Grp
13 7 nnzd G Grp A X N O A O A
14 6 7 nndivred G Grp A X N O A N O A
15 14 flcld G Grp A X N O A N O A
16 13 15 zmulcld G Grp A X N O A O A N O A
17 simpl2 G Grp A X N O A A X
18 eqid - G = - G
19 1 3 18 mulgsubdir G Grp N O A N O A A X N O A N O A · ˙ A = N · ˙ A - G O A N O A · ˙ A
20 12 5 16 17 19 syl13anc G Grp A X N O A N O A N O A · ˙ A = N · ˙ A - G O A N O A · ˙ A
21 nncn O A O A
22 zcn N O A N O A
23 mulcom O A N O A O A N O A = N O A O A
24 21 22 23 syl2an O A N O A O A N O A = N O A O A
25 7 15 24 syl2anc G Grp A X N O A O A N O A = N O A O A
26 25 oveq1d G Grp A X N O A O A N O A · ˙ A = N O A O A · ˙ A
27 1 3 mulgass G Grp N O A O A A X N O A O A · ˙ A = N O A · ˙ O A · ˙ A
28 12 15 13 17 27 syl13anc G Grp A X N O A N O A O A · ˙ A = N O A · ˙ O A · ˙ A
29 1 2 3 4 odid A X O A · ˙ A = 0 ˙
30 17 29 syl G Grp A X N O A O A · ˙ A = 0 ˙
31 30 oveq2d G Grp A X N O A N O A · ˙ O A · ˙ A = N O A · ˙ 0 ˙
32 1 3 4 mulgz G Grp N O A N O A · ˙ 0 ˙ = 0 ˙
33 12 15 32 syl2anc G Grp A X N O A N O A · ˙ 0 ˙ = 0 ˙
34 31 33 eqtrd G Grp A X N O A N O A · ˙ O A · ˙ A = 0 ˙
35 26 28 34 3eqtrd G Grp A X N O A O A N O A · ˙ A = 0 ˙
36 35 oveq2d G Grp A X N O A N · ˙ A - G O A N O A · ˙ A = N · ˙ A - G 0 ˙
37 1 3 mulgcl G Grp N A X N · ˙ A X
38 12 5 17 37 syl3anc G Grp A X N O A N · ˙ A X
39 1 4 18 grpsubid1 G Grp N · ˙ A X N · ˙ A - G 0 ˙ = N · ˙ A
40 12 38 39 syl2anc G Grp A X N O A N · ˙ A - G 0 ˙ = N · ˙ A
41 36 40 eqtrd G Grp A X N O A N · ˙ A - G O A N O A · ˙ A = N · ˙ A
42 11 20 41 3eqtrd G Grp A X N O A N mod O A · ˙ A = N · ˙ A