Metamath Proof Explorer


Theorem motplusg

Description: The operation for motions is their composition. (Contributed by Thierry Arnoux, 15-Dec-2019)

Ref Expression
Hypotheses ismot.p P = Base G
ismot.m - ˙ = dist G
motgrp.1 φ G V
motgrp.i I = Base ndx G Ismt G + ndx f G Ismt G , g G Ismt G f g
motplusg.1 φ F G Ismt G
motplusg.2 φ H G Ismt G
Assertion motplusg φ F + I H = F H

Proof

Step Hyp Ref Expression
1 ismot.p P = Base G
2 ismot.m - ˙ = dist G
3 motgrp.1 φ G V
4 motgrp.i I = Base ndx G Ismt G + ndx f G Ismt G , g G Ismt G f g
5 motplusg.1 φ F G Ismt G
6 motplusg.2 φ H G Ismt G
7 coexg F G Ismt G H G Ismt G F H V
8 5 6 7 syl2anc φ F H V
9 coeq1 a = F a b = F b
10 coeq2 b = H F b = F H
11 ovex G Ismt G V
12 11 11 mpoex f G Ismt G , g G Ismt G f g V
13 4 grpplusg f G Ismt G , g G Ismt G f g V f G Ismt G , g G Ismt G f g = + I
14 12 13 ax-mp f G Ismt G , g G Ismt G f g = + I
15 coeq1 f = a f g = a g
16 coeq2 g = b a g = a b
17 15 16 cbvmpov f G Ismt G , g G Ismt G f g = a G Ismt G , b G Ismt G a b
18 14 17 eqtr3i + I = a G Ismt G , b G Ismt G a b
19 9 10 18 ovmpog F G Ismt G H G Ismt G F H V F + I H = F H
20 5 6 8 19 syl3anc φ F + I H = F H