Metamath Proof Explorer


Theorem motf1o

Description: Motions are bijections. (Contributed by Thierry Arnoux, 15-Dec-2019)

Ref Expression
Hypotheses ismot.p ⊢ 𝑃 = ( Base ‘ 𝐺 )
ismot.m ⊢ − = ( dist ‘ 𝐺 )
motgrp.1 ⊢ ( 𝜑 → 𝐺 ∈ 𝑉 )
motco.2 ⊢ ( 𝜑 → 𝐹 ∈ ( 𝐺 Ismt 𝐺 ) )
Assertion motf1o ( 𝜑 → 𝐹 : 𝑃 –1-1-onto→ 𝑃 )

Proof

Step Hyp Ref Expression
1 ismot.p ⊢ 𝑃 = ( Base ‘ 𝐺 )
2 ismot.m ⊢ − = ( dist ‘ 𝐺 )
3 motgrp.1 ⊢ ( 𝜑 → 𝐺 ∈ 𝑉 )
4 motco.2 ⊢ ( 𝜑 → 𝐹 ∈ ( 𝐺 Ismt 𝐺 ) )
5 1 2 ismot ⊢ ( 𝐺 ∈ 𝑉 → ( 𝐹 ∈ ( 𝐺 Ismt 𝐺 ) ↔ ( 𝐹 : 𝑃 –1-1-onto→ 𝑃 ∧ ∀ 𝑎 ∈ 𝑃 ∀ 𝑏 ∈ 𝑃 ( ( 𝐹 ‘ 𝑎 ) − ( 𝐹 ‘ 𝑏 ) ) = ( 𝑎 − 𝑏 ) ) ) )
6 3 5 syl ⊢ ( 𝜑 → ( 𝐹 ∈ ( 𝐺 Ismt 𝐺 ) ↔ ( 𝐹 : 𝑃 –1-1-onto→ 𝑃 ∧ ∀ 𝑎 ∈ 𝑃 ∀ 𝑏 ∈ 𝑃 ( ( 𝐹 ‘ 𝑎 ) − ( 𝐹 ‘ 𝑏 ) ) = ( 𝑎 − 𝑏 ) ) ) )
7 4 6 mpbid ⊢ ( 𝜑 → ( 𝐹 : 𝑃 –1-1-onto→ 𝑃 ∧ ∀ 𝑎 ∈ 𝑃 ∀ 𝑏 ∈ 𝑃 ( ( 𝐹 ‘ 𝑎 ) − ( 𝐹 ‘ 𝑏 ) ) = ( 𝑎 − 𝑏 ) ) )
8 7 simpld ⊢ ( 𝜑 → 𝐹 : 𝑃 –1-1-onto→ 𝑃 )