Metamath Proof Explorer


Theorem colinrel

Description: Colinearity is a relationship. (Contributed by Scott Fenton, 7-Nov-2013) (Revised by Mario Carneiro, 19-Apr-2014)

Ref Expression
Assertion colinrel Rel Colinear

Proof

Step Hyp Ref Expression
1 relcnv Rel { ⟨ ⟨ 𝑞 , 𝑟 ⟩ , 𝑝 ⟩ ∣ ∃ 𝑛 ∈ ℕ ( ( 𝑝 ∈ ( 𝔼 ‘ 𝑛 ) ∧ 𝑞 ∈ ( 𝔼 ‘ 𝑛 ) ∧ 𝑟 ∈ ( 𝔼 ‘ 𝑛 ) ) ∧ ( 𝑝 Btwn ⟨ 𝑞 , 𝑟 ⟩ ∨ 𝑞 Btwn ⟨ 𝑟 , 𝑝 ⟩ ∨ 𝑟 Btwn ⟨ 𝑝 , 𝑞 ⟩ ) ) }
2 df-colinear Colinear = { ⟨ ⟨ 𝑞 , 𝑟 ⟩ , 𝑝 ⟩ ∣ ∃ 𝑛 ∈ ℕ ( ( 𝑝 ∈ ( 𝔼 ‘ 𝑛 ) ∧ 𝑞 ∈ ( 𝔼 ‘ 𝑛 ) ∧ 𝑟 ∈ ( 𝔼 ‘ 𝑛 ) ) ∧ ( 𝑝 Btwn ⟨ 𝑞 , 𝑟 ⟩ ∨ 𝑞 Btwn ⟨ 𝑟 , 𝑝 ⟩ ∨ 𝑟 Btwn ⟨ 𝑝 , 𝑞 ⟩ ) ) }
3 2 releqi ( Rel Colinear ↔ Rel { ⟨ ⟨ 𝑞 , 𝑟 ⟩ , 𝑝 ⟩ ∣ ∃ 𝑛 ∈ ℕ ( ( 𝑝 ∈ ( 𝔼 ‘ 𝑛 ) ∧ 𝑞 ∈ ( 𝔼 ‘ 𝑛 ) ∧ 𝑟 ∈ ( 𝔼 ‘ 𝑛 ) ) ∧ ( 𝑝 Btwn ⟨ 𝑞 , 𝑟 ⟩ ∨ 𝑞 Btwn ⟨ 𝑟 , 𝑝 ⟩ ∨ 𝑟 Btwn ⟨ 𝑝 , 𝑞 ⟩ ) ) } )
4 1 3 mpbir Rel Colinear