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