Metamath Proof Explorer


Theorem tgrpabl

Description: The translation group is an Abelian group. Lemma G of Crawley p. 116. (Contributed by NM, 6-Jun-2013)

Ref Expression
Hypotheses tgrpgrp.h H = LHyp K
tgrpgrp.g G = TGrp K W
Assertion tgrpabl K HL W H G Abel

Proof

Step Hyp Ref Expression
1 tgrpgrp.h H = LHyp K
2 tgrpgrp.g G = TGrp K W
3 eqid LTrn K W = LTrn K W
4 eqid Base G = Base G
5 1 3 2 4 tgrpbase K HL W H Base G = LTrn K W
6 5 eqcomd K HL W H LTrn K W = Base G
7 eqidd K HL W H + G = + G
8 1 2 tgrpgrp K HL W H G Grp
9 1 3 ltrncom K HL W H f LTrn K W g LTrn K W f g = g f
10 eqid + G = + G
11 1 3 2 10 tgrpov K HL W H f LTrn K W g LTrn K W f + G g = f g
12 11 3expa K HL W H f LTrn K W g LTrn K W f + G g = f g
13 12 3impb K HL W H f LTrn K W g LTrn K W f + G g = f g
14 1 3 2 10 tgrpov K HL W H g LTrn K W f LTrn K W g + G f = g f
15 14 3expa K HL W H g LTrn K W f LTrn K W g + G f = g f
16 15 3impb K HL W H g LTrn K W f LTrn K W g + G f = g f
17 16 3com23 K HL W H f LTrn K W g LTrn K W g + G f = g f
18 9 13 17 3eqtr4d K HL W H f LTrn K W g LTrn K W f + G g = g + G f
19 6 7 8 18 isabld K HL W H G Abel