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lemma proved tactic proof

cone_bound

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formal statement (Lean)

  75lemma cone_bound
  76  (H : StepBounds K U time rad)
  77  {n x y} (h : Local.ReachN K n x y) :
  78  rad y - rad x ≤ U.c * (time y - time x) := by

proof body

Tactic-mode proof.

  79  have ht := H.reach_time_eq (K:=K) (U:=U) (time:=time) (rad:=rad) h
  80  have hr := H.reach_rad_le  (K:=K) (U:=U) (time:=time) (rad:=rad) h
  81  have hτ : time y - time x = (n : ℝ) * U.tau0 := by
  82    have := congrArg (fun t => t - time x) ht
  83    simpa [sub_eq_add_neg, add_comm, add_left_comm, add_assoc] using this
  84  have hℓ : rad y - rad x ≤ (n : ℝ) * U.ell0 := by
  85    have := hr
  86    -- rearrange ≤ to a difference inequality
  87    have := sub_le_iff_le_add'.mpr this
  88    simpa [sub_eq_add_neg, add_comm, add_left_comm, add_assoc]
  89  -- In minimal RSUnits, ell0 = c * tau0 is available as the supplied field
  90  have hcτ : U.ell0 = U.c * U.tau0 := by simpa using (U.c_ell0_tau0).symm
  91  simpa [hτ, hcτ, mul_left_comm, mul_assoc] using hℓ
  92
  93/-- Saturation lemma restated: equality holds when each step exactly reaches its bounds. -/

used by (2)

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depends on (30)

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