Module: Mathlib.Data.EReal.Operations

Goal state before:
pp: case inl.inl
a b : EReal
h : a < 0
h' : b < 0
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

pp: case inl.inr.inl
a b : EReal
h : a < 0
h' : b = 0
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

pp: case inl.inr.inr
a b : EReal
h : a < 0
h' : 0 < b
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

pp: case inr.inl.inl
a b : EReal
h : a = 0
h' : b < 0
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

pp: case inr.inl.inr.inl
a b : EReal
h : a = 0
h' : b = 0
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

pp: case inr.inl.inr.inr
a b : EReal
h : a = 0
h' : 0 < b
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

pp: case inr.inr.inl
a b : EReal
h : 0 < a
h' : b < 0
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

pp: case inr.inr.inr.inl
a b : EReal
h : 0 < a
h' : b = 0
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

pp: case inr.inr.inr.inr
a b : EReal
h : 0 < a
h' : 0 < b
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

Tactic:
<;>

Goal state after:
case inl.inl
a b : EReal
h : a < 0
h' : b < 0
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

case inl.inr.inl
a b : EReal
h : a < 0
h' : b = 0
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

case inl.inr.inr
a b : EReal
h : a < 0
h' : 0 < b
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

case inr.inl.inl
a b : EReal
h : a = 0
h' : b < 0
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

case inr.inl.inr.inl
a b : EReal
h : a = 0
h' : b = 0
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

case inr.inl.inr.inr
a b : EReal
h : a = 0
h' : 0 < b
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

case inr.inr.inl
a b : EReal
h : 0 < a
h' : b < 0
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

case inr.inr.inr.inl
a b : EReal
h : 0 < a
h' : b = 0
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)

case inr.inr.inr.inr
a b : EReal
h : 0 < a
h' : 0 < b
⊢ (0 < a ∧ 0 < b ∨ a < 0 ∧ b < 0) ∨ a = 0 ∨ b = 0 ↔
    (0 < a ∨ 0 = a) ∧ (0 < b ∨ 0 = b) ∨ (a < 0 ∨ a = 0) ∧ (b < 0 ∨ b = 0)