case mk
ι : Type u_1
J : Box ι
x y l u lI uI : ι → ℝ
hI : ∀ (i : ι), lI i < uI i
⊢ mk' l u = ↑{ lower := lI, upper := uI, lower_lt_upper := hI } ↔
    l = { lower := lI, upper := uI, lower_lt_upper := hI }.lower ∧
      u = { lower := lI, upper := uI, lower_lt_upper := hI }.upper
ι : Type u_1
I J : Box ι
x y l u : ι → ℝ
⊢ mk' l u = ↑I ↔ l = I.lower ∧ u = I.upper
cases' I with lI uI hI
case mk
ι : Type u_1
J : Box ι
x y l u lI uI : ι → ℝ
hI : ∀ (i : ι), lI i < uI i
⊢ (if h : ∀ (i : ι), l i < u i then ↑{ lower := l, upper := u, lower_lt_upper := h } else ⊥) =
      ↑{ lower := lI, upper := uI, lower_lt_upper := hI } ↔
    l = { lower := lI, upper := uI, lower_lt_upper := hI }.lower ∧
      u = { lower := lI, upper := uI, lower_lt_upper := hI }.upper
case mk
ι : Type u_1
J : Box ι
x y l u lI uI : ι → ℝ
hI : ∀ (i : ι), lI i < uI i
⊢ mk' l u = ↑{ lower := lI, upper := uI, lower_lt_upper := hI } ↔
    l = { lower := lI, upper := uI, lower_lt_upper := hI }.lower ∧
      u = { lower := lI, upper := uI, lower_lt_upper := hI }.upper
rw [mk']
case mk.inl
ι : Type u_1
J : Box ι
x y l u lI uI : ι → ℝ
hI : ∀ (i : ι), lI i < uI i
h : ∀ (i : ι), l i < u i
⊢ ↑{ lower := l, upper := u, lower_lt_upper := h } = ↑{ lower := lI, upper := uI, lower_lt_upper := hI } ↔
    l = { lower := lI, upper := uI, lower_lt_upper := hI }.lower ∧
      u = { lower := lI, upper := uI, lower_lt_upper := hI }.upper

case mk.inr
ι : Type u_1
J : Box ι
x y l u lI uI : ι → ℝ
hI : ∀ (i : ι), lI i < uI i
h : ¬∀ (i : ι), l i < u i
⊢ ⊥ = ↑{ lower := lI, upper := uI, lower_lt_upper := hI } ↔
    l = { lower := lI, upper := uI, lower_lt_upper := hI }.lower ∧
      u = { lower := lI, upper := uI, lower_lt_upper := hI }.upper
case mk
ι : Type u_1
J : Box ι
x y l u lI uI : ι → ℝ
hI : ∀ (i : ι), lI i < uI i
⊢ (if h : ∀ (i : ι), l i < u i then ↑{ lower := l, upper := u, lower_lt_upper := h } else ⊥) =
      ↑{ lower := lI, upper := uI, lower_lt_upper := hI } ↔
    l = { lower := lI, upper := uI, lower_lt_upper := hI }.lower ∧
      u = { lower := lI, upper := uI, lower_lt_upper := hI }.upper
split_ifs with h
no goals
case mk.inl
ι : Type u_1
J : Box ι
x y l u lI uI : ι → ℝ
hI : ∀ (i : ι), lI i < uI i
h : ∀ (i : ι), l i < u i
⊢ ↑{ lower := l, upper := u, lower_lt_upper := h } = ↑{ lower := lI, upper := uI, lower_lt_upper := hI } ↔
    l = { lower := lI, upper := uI, lower_lt_upper := hI }.lower ∧
      u = { lower := lI, upper := uI, lower_lt_upper := hI }.upper
simp [WithBot.coe_eq_coe]
case mk.inr
ι : Type u_1
J : Box ι
x y l u lI uI : ι → ℝ
hI : ∀ (i : ι), lI i < uI i
h : ¬∀ (i : ι), l i < u i
⊢ l = lI → u ≠ uI
case mk.inr
ι : Type u_1
J : Box ι
x y l u lI uI : ι → ℝ
hI : ∀ (i : ι), lI i < uI i
h : ¬∀ (i : ι), l i < u i
⊢ ⊥ = ↑{ lower := lI, upper := uI, lower_lt_upper := hI } ↔
    l = { lower := lI, upper := uI, lower_lt_upper := hI }.lower ∧
      u = { lower := lI, upper := uI, lower_lt_upper := hI }.upper
suffices l = lI → u ≠ uI by simpa
case mk.inr
ι : Type u_1
J : Box ι
x y l u : ι → ℝ
h : ¬∀ (i : ι), l i < u i
hI : ∀ (i : ι), l i < u i
⊢ False
case mk.inr
ι : Type u_1
J : Box ι
x y l u lI uI : ι → ℝ
hI : ∀ (i : ι), lI i < uI i
h : ¬∀ (i : ι), l i < u i
⊢ l = lI → u ≠ uI
rintro rfl rfl
no goals
case mk.inr
ι : Type u_1
J : Box ι
x y l u : ι → ℝ
h : ¬∀ (i : ι), l i < u i
hI : ∀ (i : ι), l i < u i
⊢ False
exact h hI
no goals
ι : Type u_1
J : Box ι
x y l u lI uI : ι → ℝ
hI : ∀ (i : ι), lI i < uI i
h : ¬∀ (i : ι), l i < u i
this : l = lI → u ≠ uI
⊢ ⊥ = ↑{ lower := lI, upper := uI, lower_lt_upper := hI } ↔
    l = { lower := lI, upper := uI, lower_lt_upper := hI }.lower ∧
      u = { lower := lI, upper := uI, lower_lt_upper := hI }.upper
simpa