Theorem btwncolinear1 36539

Description: Betweenness implies colinearity. (Contributed by Scott Fenton, 7-Oct-2013.)

Assertion

Ref	Expression
btwncolinear1	⊢ ((𝑁 ∈ ℕ ∧ (𝐴 ∈ (𝔼‘𝑁) ∧ 𝐵 ∈ (𝔼‘𝑁) ∧ 𝐶 ∈ (𝔼‘𝑁))) → (𝐶 Btwn ⟨𝐴, 𝐵⟩ → 𝐴 Colinear ⟨𝐵, 𝐶⟩))

Proof of Theorem btwncolinear1

Step	Hyp	Ref	Expression
1		3mix3 1351	. 2 ⊢ (𝐶 Btwn ⟨𝐴, 𝐵⟩ → (𝐴 Btwn ⟨𝐵, 𝐶⟩ ∨ 𝐵 Btwn ⟨𝐶, 𝐴⟩ ∨ 𝐶 Btwn ⟨𝐴, 𝐵⟩))
2		brcolinear 36529	. 2 ⊢ ((𝑁 ∈ ℕ ∧ (𝐴 ∈ (𝔼‘𝑁) ∧ 𝐵 ∈ (𝔼‘𝑁) ∧ 𝐶 ∈ (𝔼‘𝑁))) → (𝐴 Colinear ⟨𝐵, 𝐶⟩ ↔ (𝐴 Btwn ⟨𝐵, 𝐶⟩ ∨ 𝐵 Btwn ⟨𝐶, 𝐴⟩ ∨ 𝐶 Btwn ⟨𝐴, 𝐵⟩)))
3	1, 2	imbitrrid 249	1 ⊢ ((𝑁 ∈ ℕ ∧ (𝐴 ∈ (𝔼‘𝑁) ∧ 𝐵 ∈ (𝔼‘𝑁) ∧ 𝐶 ∈ (𝔼‘𝑁))) → (𝐶 Btwn ⟨𝐴, 𝐵⟩ → 𝐴 Colinear ⟨𝐵, 𝐶⟩))

Syntax hints:   → wi 4   ∧ wa 400   ∨ w3o 1102   ∧ w3a 1103   ∈ wcel 2143  ⟨cop 4596   class class class wbr 5110  ‘cfv 6538  ℕcn 12234  𝔼cee 29215   Btwn cbtwn 29216   Colinear ccolin 36507

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1825  ax-4 1839  ax-5 1940  ax-6 1997  ax-7 2038  ax-8 2145  ax-9 2153  ax-12 2213  ax-ext 2735  ax-sep 5258  ax-pr 5406

This theorem depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3or 1104  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1810  df-sb 2097  df-clab 2742  df-cleq 2755  df-clel 2838  df-ral 3080  df-rex 3090  df-rab 3417  df-v 3457  df-dif 3909  df-un 3911  df-in 3913  df-ss 3923  df-nul 4288  df-if 4489  df-sn 4591  df-pr 4593  df-op 4597  df-uni 4874  df-br 5111  df-opab 5175  df-xp 5669  df-rel 5670  df-cnv 5671  df-iota 6494  df-fv 6546  df-oprab 7416  df-colinear 36509

This theorem is referenced by:  btwncolinear2  36540  btwncolinear3  36541  btwncolinear4  36542  btwncolinear5  36543  btwncolinear6  36544  idinside  36554  btwnconn1lem12  36568  brsegle2  36579  broutsideof2  36592  outsidele  36602