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