Metamath Proof Explorer


Theorem ngpinvds

Description: Two elements are the same distance apart as their inverses. (Contributed by Mario Carneiro, 4-Oct-2015)

Ref Expression
Hypotheses ngpinvds.x X=BaseG
ngpinvds.i I=invgG
ngpinvds.d D=distG
Assertion ngpinvds GNrmGrpGAbelAXBXIADIB=ADB

Proof

Step Hyp Ref Expression
1 ngpinvds.x X=BaseG
2 ngpinvds.i I=invgG
3 ngpinvds.d D=distG
4 eqid -G=-G
5 simplr GNrmGrpGAbelAXBXGAbel
6 simprr GNrmGrpGAbelAXBXBX
7 simprl GNrmGrpGAbelAXBXAX
8 1 4 2 5 6 7 ablsub2inv GNrmGrpGAbelAXBXIB-GIA=A-GB
9 8 fveq2d GNrmGrpGAbelAXBXnormGIB-GIA=normGA-GB
10 simpll GNrmGrpGAbelAXBXGNrmGrp
11 ngpgrp GNrmGrpGGrp
12 10 11 syl GNrmGrpGAbelAXBXGGrp
13 1 2 grpinvcl GGrpAXIAX
14 12 7 13 syl2anc GNrmGrpGAbelAXBXIAX
15 1 2 grpinvcl GGrpBXIBX
16 12 6 15 syl2anc GNrmGrpGAbelAXBXIBX
17 eqid normG=normG
18 17 1 4 3 ngpdsr GNrmGrpIAXIBXIADIB=normGIB-GIA
19 10 14 16 18 syl3anc GNrmGrpGAbelAXBXIADIB=normGIB-GIA
20 17 1 4 3 ngpds GNrmGrpAXBXADB=normGA-GB
21 10 7 6 20 syl3anc GNrmGrpGAbelAXBXADB=normGA-GB
22 9 19 21 3eqtr4d GNrmGrpGAbelAXBXIADIB=ADB