Metamath Proof Explorer


Theorem lsm4

Description: Commutative/associative law for subgroup sum. (Contributed by NM, 26-Sep-2014) (Revised by Mario Carneiro, 19-Apr-2016)

Ref Expression
Hypothesis lsmcom.s ˙=LSSumG
Assertion lsm4 GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGQ˙R˙T˙U=Q˙T˙R˙U

Proof

Step Hyp Ref Expression
1 lsmcom.s ˙=LSSumG
2 simp1 GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGGAbel
3 simp2r GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGRSubGrpG
4 simp3l GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGTSubGrpG
5 1 lsmcom GAbelRSubGrpGTSubGrpGR˙T=T˙R
6 2 3 4 5 syl3anc GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGR˙T=T˙R
7 6 oveq2d GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGQ˙R˙T=Q˙T˙R
8 simp2l GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGQSubGrpG
9 1 lsmass QSubGrpGRSubGrpGTSubGrpGQ˙R˙T=Q˙R˙T
10 8 3 4 9 syl3anc GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGQ˙R˙T=Q˙R˙T
11 1 lsmass QSubGrpGTSubGrpGRSubGrpGQ˙T˙R=Q˙T˙R
12 8 4 3 11 syl3anc GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGQ˙T˙R=Q˙T˙R
13 7 10 12 3eqtr4d GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGQ˙R˙T=Q˙T˙R
14 13 oveq1d GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGQ˙R˙T˙U=Q˙T˙R˙U
15 1 lsmsubg2 GAbelQSubGrpGRSubGrpGQ˙RSubGrpG
16 2 8 3 15 syl3anc GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGQ˙RSubGrpG
17 simp3r GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGUSubGrpG
18 1 lsmass Q˙RSubGrpGTSubGrpGUSubGrpGQ˙R˙T˙U=Q˙R˙T˙U
19 16 4 17 18 syl3anc GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGQ˙R˙T˙U=Q˙R˙T˙U
20 1 lsmsubg2 GAbelQSubGrpGTSubGrpGQ˙TSubGrpG
21 2 8 4 20 syl3anc GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGQ˙TSubGrpG
22 1 lsmass Q˙TSubGrpGRSubGrpGUSubGrpGQ˙T˙R˙U=Q˙T˙R˙U
23 21 3 17 22 syl3anc GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGQ˙T˙R˙U=Q˙T˙R˙U
24 14 19 23 3eqtr3d GAbelQSubGrpGRSubGrpGTSubGrpGUSubGrpGQ˙R˙T˙U=Q˙T˙R˙U