theorem extracted_formal_statement_67.{u_3, u_2, u_1} {E₁ : Type u_1} {E₂ : Type u_2} {F : Type u_3}
  [inst : NormedAddCommGroup E₁] [inst_1 : InnerProductSpace ℝ E₁] [inst_2 : FiniteDimensional ℝ E₁]
  [inst_3 : NormedAddCommGroup E₂] [inst_4 : InnerProductSpace ℝ E₂] [inst_5 : FiniteDimensional ℝ E₂]
  [inst_6 : NormedAddCommGroup F] [inst_7 : InnerProductSpace ℝ F] [inst_8 : FiniteDimensional ℝ F]
  {admm : ADMM E₁ E₂ F} {admm_kkt : Existance_of_kkt admm} (fullrank₁ : Function.Injective ⇑(OptProblem.A₁ E₂))
  (fullrank₂ : Function.Injective ⇑(OptProblem.A₂ E₁)) [inst_9 : Setting E₁ E₂ F admm (admm_kkt₁ fullrank₁ fullrank₂)]
  (this : Tendsto (fun n => √(‖(OptProblem.A₂ E₁) (e₂ n)‖ ^ 2)) atTop (𝓝 √0)) :
  Tendsto (fun n => ‖(OptProblem.A₂ E₁) (e₂ n)‖) atTop (𝓝 0) := sorry

State before:
E₁ : Type u_1
E₂ : Type u_2
F : Type u_3
inst✝⁹ : NormedAddCommGroup E₁
inst✝⁸ : InnerProductSpace ℝ E₁
inst✝⁷ : FiniteDimensional ℝ E₁
inst✝⁶ : NormedAddCommGroup E₂
inst✝⁵ : InnerProductSpace ℝ E₂
inst✝⁴ : FiniteDimensional ℝ E₂
inst✝³ : NormedAddCommGroup F
inst✝² : InnerProductSpace ℝ F
inst✝¹ : FiniteDimensional ℝ F
admm : ADMM E₁ E₂ F
admm_kkt : Existance_of_kkt admm
fullrank₁ : Function.Injective ⇑(OptProblem.A₁ E₂)
fullrank₂ : Function.Injective ⇑(OptProblem.A₂ E₁)
inst✝ : Setting E₁ E₂ F admm (admm_kkt₁ fullrank₁ fullrank₂)
this : Tendsto (fun n => √(‖(OptProblem.A₂ E₁) (e₂ n)‖ ^ 2)) atTop (𝓝 √0)
⊢ Tendsto (fun n => ‖(OptProblem.A₂ E₁) (e₂ n)‖) atTop (𝓝 0)

Tactic: rw [Real.sqrt_zero] at this
    simp [Real.sqrt_sq] at this
    exact this

State after:

Relevant lemmas:
Real.sqrt_zero : √0 = 0
Real.sqrt_sq : ∀ {x : ℝ}, 0 ≤ x → √(x ^ 2) = x