mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Data.Nat.BinaryRec

Goal state before:
pp: motive : Nat → Sort u
zero : motive 0
one : motive 1
bit : (b : Bool) → (n : Nat) → n ≠ 0 → motive n → motive (Nat.bit b n)
b : Bool
n : Nat
h : n = 0 → b = true
ih : motive n
h' : n = 0
⊢ Nat.bit b n = Nat.bit true 0

Tactic:
h',

Goal state after:
motive : Nat → Sort u
zero : motive 0
one : motive 1
bit : (b : Bool) → (n : Nat) → n ≠ 0 → motive n → motive (Nat.bit b n)
b : Bool
n : Nat
h : n = 0 → b = true
ih : motive n
h' : n = 0
⊢ Nat.bit b 0 = Nat.bit true 0
Module: Mathlib.Data.Nat.BinaryRec

Goal state before:
pp: b : Bool
n : Nat
⊢ bit b n = 2 * n + b.toNat

Tactic:
cases b <;> rfl

Goal state after:
Module: Mathlib.Algebra.Group.Semiconj.Defs

Goal state before:
pp: G : Type u_3
inst✝ : Group G
a x : G
⊢ SemiconjBy a x (a * x * a⁻¹)

Tactic:
unfold SemiconjBy; rw [mul_assoc, inv_mul_cancel, mul_one]

Goal state after:
Module: Mathlib.Logic.Basic

Goal state before:
pp: α β : Sort u_2
γ : Sort u_3
f : α → γ
g : β → γ
x : α
y : β
h₁ : f ≍ g
h₂ : x ≍ y
⊢ f x = g y

Tactic:
cases h₂; cases h₁; rfl

Goal state after:
Module: Mathlib.Logic.Basic

Goal state before:
pp: A : Prop
B : A → Prop
⊢ (A → ∀ (h : A), B h) ↔ ∀ (h : A), B h

Tactic:
by_cases h : A

Goal state after:
case pos
A : Prop
B : A → Prop
h : A
⊢ (A → ∀ (h : A), B h) ↔ ∀ (h : A), B h

case neg
A : Prop
B : A → Prop
h : ¬A
⊢ (A → ∀ (h : A), B h) ↔ ∀ (h : A), B h
Module: Mathlib.Logic.Function.Basic

Goal state before:
pp: α : Sort u
β : α → Sort v
inst✝ : DecidableEq α
f : (a : α) → β a
a : α
b : β a
p : (a : α) → β a → Prop
⊢ (p a b ∧ ∀ (b_1 : α), b_1 ≠ a → p b_1 (update f a b b_1)) ↔ p a b ∧ ∀ (x : α), x ≠ a → p x (f x)

Tactic:
simp +contextual

Goal state after:
Module: Mathlib.Logic.Function.Iterate

Goal state before:
pp: α : Type u
f : α → α
m n : ℕ
⊢ f^[n * m] = f^[m * n]

Tactic:
rw [Nat.mul_comm]

Goal state after:
Module: Mathlib.Data.Sum.Basic

Goal state before:
pp: α : Type u
β : Type v
γ : Type u_1
inst✝¹ : DecidableEq α
inst✝ : DecidableEq (α ⊕ β)
f : α → γ
g : β → γ
i : α
x : γ
⊢ ∀ (x_1 : α ⊕ β), x_1 ≠ inl i → Sum.elim f g x_1 = Sum.elim (update f i x) g x_1

Tactic:
simp +contextual

Goal state after:
Module: Mathlib.Data.Sum.Basic

Goal state before:
pp: α : Type u
β : Type v
γ : Type u_1
inst✝¹ : DecidableEq β
inst✝ : DecidableEq (α ⊕ β)
f : α → γ
g : β → γ
i : β
x : γ
⊢ ∀ (x_1 : α ⊕ β), x_1 ≠ inr i → Sum.elim f g x_1 = Sum.elim f (update g i x) x_1

Tactic:
simp +contextual

Goal state after:
Module: Mathlib.Data.Prod.Basic

Goal state before:
pp: case inr.inl
α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
r✝ : α → α → Prop
s✝ : β → β → Prop
x y : α × β
r : α → α → Prop
s : β → β → Prop
inst✝¹ : Std.Trichotomous r
inst✝ : Std.Total s
x✝¹ x✝ : α × β
i : α
a b : β
⊢ Prod.Lex r s (i, a) (i, b) ∨ Prod.Lex r s (i, b) (i, a)

Tactic:
exact (total_of s a b).imp (.right _) (.right _)

Goal state after:
Module: Mathlib.Order.Defs.LinearOrder

Goal state before:
pp: case pos
α : Type u_1
inst✝ : LinearOrder α
a b : α
motive : α → Prop
ha : a ≤ b → motive a
hb : b ≤ a → motive b
h : a ≤ b
⊢ motive a

pp: case neg
α : Type u_1
inst✝ : LinearOrder α
a b : α
motive : α → Prop
ha : a ≤ b → motive a
hb : b ≤ a → motive b
h : ¬a ≤ b
⊢ motive b

Tactic:
exacts [ha h, hb (le_of_not_ge h)]

Goal state after:
Module: Mathlib.Order.Defs.LinearOrder

Goal state before:
pp: case gt
α : Type u_1
inst✝ : LinearOrder α
a b : α
h : compare a b = Ordering.gt
⊢ Ordering.gt ≠ Ordering.lt ↔ b ≤ a

Tactic:
· simpa using le_of_lt <| compare_gt_iff_gt.1 h

Goal state after:
Module: Mathlib.Data.Bool.Basic

Goal state before:
pp: b : Bool
⊢ (b.toNat == 1) = b

Tactic:
cases b <;> rfl

Goal state after:
Module: Mathlib.Data.Set.Basic

Goal state before:
pp: α : Type u
s : Set α
⊢ ¬Nonempty ↑s ↔ s = ∅

Tactic:
nonempty_subtype,

Goal state after:
α : Type u
s : Set α
⊢ (¬∃ a, a ∈ s) ↔ s = ∅
Module: Mathlib.Order.Lattice

Goal state before:
pp: α✝ : Type u
β : Type v
α : Type u_1
inst✝ : Max α
sup_comm : ∀ (a b : α), a ⊔ b = b ⊔ a
sup_assoc : ∀ (a b c : α), a ⊔ b ⊔ c = a ⊔ (b ⊔ c)
sup_idem : ∀ (a : α), a ⊔ a = a
a b : α
⊢ b ⊔ (a ⊔ b) = a ⊔ b

Tactic:
rw [sup_comm, sup_assoc, sup_idem]

Goal state after:
Module: Mathlib.Order.Lattice

Goal state before:
pp: α✝ : Type u
β : Type v
α : Type u_1
inst✝¹ : Max α
inst✝ : Min α
sup_comm : ∀ (a b : α), a ⊔ b = b ⊔ a
sup_assoc : ∀ (a b c : α), a ⊔ b ⊔ c = a ⊔ (b ⊔ c)
inf_comm : ∀ (a b : α), a ⊓ b = b ⊓ a
inf_assoc : ∀ (a b c : α), a ⊓ b ⊓ c = a ⊓ (b ⊓ c)
sup_inf_self : ∀ (a b : α), a ⊔ a ⊓ b = a
inf_sup_self : ∀ (a b : α), a ⊓ (a ⊔ b) = a
sup_idem : ∀ (b : α), b ⊔ b = b
inf_idem : ∀ (b : α), b ⊓ b = b
semilatt_inf_inst : SemilatticeInf α := SemilatticeInf.mk' inf_comm inf_assoc inf_idem
semilatt_sup_inst : SemilatticeSup α := SemilatticeSup.mk' sup_comm sup_assoc sup_idem
partial_order_eq : semilatt_sup_inst.toPartialOrder = semilatt_inf_inst.toPartialOrder
a b : α
⊢ SemilatticeInf.inf a b ≤ a

Tactic:
rw [partial_order_eq]

Goal state after:
α✝ : Type u
β : Type v
α : Type u_1
inst✝¹ : Max α
inst✝ : Min α
sup_comm : ∀ (a b : α), a ⊔ b = b ⊔ a
sup_assoc : ∀ (a b c : α), a ⊔ b ⊔ c = a ⊔ (b ⊔ c)
inf_comm : ∀ (a b : α), a ⊓ b = b ⊓ a
inf_assoc : ∀ (a b c : α), a ⊓ b ⊓ c = a ⊓ (b ⊓ c)
sup_inf_self : ∀ (a b : α), a ⊔ a ⊓ b = a
inf_sup_self : ∀ (a b : α), a ⊓ (a ⊔ b) = a
sup_idem : ∀ (b : α), b ⊔ b = b
inf_idem : ∀ (b : α), b ⊓ b = b
semilatt_inf_inst : SemilatticeInf α := SemilatticeInf.mk' inf_comm inf_assoc inf_idem
semilatt_sup_inst : SemilatticeSup α := SemilatticeSup.mk' sup_comm sup_assoc sup_idem
partial_order_eq : semilatt_sup_inst.toPartialOrder = semilatt_inf_inst.toPartialOrder
a b : α
⊢ SemilatticeInf.inf a b ≤ a
Module: Mathlib.Order.Lattice

Goal state before:
pp: α✝ : Type u
β : Type v
α : Type u_1
inst✝¹ : Max α
inst✝ : Min α
sup_comm : ∀ (a b : α), a ⊔ b = b ⊔ a
sup_assoc : ∀ (a b c : α), a ⊔ b ⊔ c = a ⊔ (b ⊔ c)
inf_comm : ∀ (a b : α), a ⊓ b = b ⊓ a
inf_assoc : ∀ (a b c : α), a ⊓ b ⊓ c = a ⊓ (b ⊓ c)
sup_inf_self : ∀ (a b : α), a ⊔ a ⊓ b = a
inf_sup_self : ∀ (a b : α), a ⊓ (a ⊔ b) = a
sup_idem : ∀ (b : α), b ⊔ b = b
inf_idem : ∀ (b : α), b ⊓ b = b
semilatt_inf_inst : SemilatticeInf α := SemilatticeInf.mk' inf_comm inf_assoc inf_idem
semilatt_sup_inst : SemilatticeSup α := SemilatticeSup.mk' sup_comm sup_assoc sup_idem
partial_order_eq : semilatt_sup_inst.toPartialOrder = semilatt_inf_inst.toPartialOrder
a b : α
⊢ SemilatticeInf.inf a b ≤ b

Tactic:
rw [partial_order_eq]

Goal state after:
α✝ : Type u
β : Type v
α : Type u_1
inst✝¹ : Max α
inst✝ : Min α
sup_comm : ∀ (a b : α), a ⊔ b = b ⊔ a
sup_assoc : ∀ (a b c : α), a ⊔ b ⊔ c = a ⊔ (b ⊔ c)
inf_comm : ∀ (a b : α), a ⊓ b = b ⊓ a
inf_assoc : ∀ (a b c : α), a ⊓ b ⊓ c = a ⊓ (b ⊓ c)
sup_inf_self : ∀ (a b : α), a ⊔ a ⊓ b = a
inf_sup_self : ∀ (a b : α), a ⊓ (a ⊔ b) = a
sup_idem : ∀ (b : α), b ⊔ b = b
inf_idem : ∀ (b : α), b ⊓ b = b
semilatt_inf_inst : SemilatticeInf α := SemilatticeInf.mk' inf_comm inf_assoc inf_idem
semilatt_sup_inst : SemilatticeSup α := SemilatticeSup.mk' sup_comm sup_assoc sup_idem
partial_order_eq : semilatt_sup_inst.toPartialOrder = semilatt_inf_inst.toPartialOrder
a b : α
⊢ SemilatticeInf.inf a b ≤ b
Module: Mathlib.Order.Lattice

Goal state before:
pp: α✝ : Type u
β : Type v
α : Type u_1
inst✝¹ : Max α
inst✝ : Min α
sup_comm : ∀ (a b : α), a ⊔ b = b ⊔ a
sup_assoc : ∀ (a b c : α), a ⊔ b ⊔ c = a ⊔ (b ⊔ c)
inf_comm : ∀ (a b : α), a ⊓ b = b ⊓ a
inf_assoc : ∀ (a b c : α), a ⊓ b ⊓ c = a ⊓ (b ⊓ c)
sup_inf_self : ∀ (a b : α), a ⊔ a ⊓ b = a
inf_sup_self : ∀ (a b : α), a ⊓ (a ⊔ b) = a
sup_idem : ∀ (b : α), b ⊔ b = b
inf_idem : ∀ (b : α), b ⊓ b = b
semilatt_inf_inst : SemilatticeInf α := SemilatticeInf.mk' inf_comm inf_assoc inf_idem
semilatt_sup_inst : SemilatticeSup α := SemilatticeSup.mk' sup_comm sup_assoc sup_idem
partial_order_eq : semilatt_sup_inst.toPartialOrder = semilatt_inf_inst.toPartialOrder
a b c : α
⊢ a ≤ b → a ≤ c → a ≤ SemilatticeInf.inf b c

Tactic:
rw [partial_order_eq]

Goal state after:
α✝ : Type u
β : Type v
α : Type u_1
inst✝¹ : Max α
inst✝ : Min α
sup_comm : ∀ (a b : α), a ⊔ b = b ⊔ a
sup_assoc : ∀ (a b c : α), a ⊔ b ⊔ c = a ⊔ (b ⊔ c)
inf_comm : ∀ (a b : α), a ⊓ b = b ⊓ a
inf_assoc : ∀ (a b c : α), a ⊓ b ⊓ c = a ⊓ (b ⊓ c)
sup_inf_self : ∀ (a b : α), a ⊔ a ⊓ b = a
inf_sup_self : ∀ (a b : α), a ⊓ (a ⊔ b) = a
sup_idem : ∀ (b : α), b ⊔ b = b
inf_idem : ∀ (b : α), b ⊓ b = b
semilatt_inf_inst : SemilatticeInf α := SemilatticeInf.mk' inf_comm inf_assoc inf_idem
semilatt_sup_inst : SemilatticeSup α := SemilatticeSup.mk' sup_comm sup_assoc sup_idem
partial_order_eq : semilatt_sup_inst.toPartialOrder = semilatt_inf_inst.toPartialOrder
a b c : α
⊢ a ≤ b → a ≤ c → a ≤ SemilatticeInf.inf b c
Module: Mathlib.Order.Lattice

Goal state before:
pp: α : Type u
β : Type v
f : α → β
s : Set α
x y : α
inst✝¹ : LinearOrder α
inst✝ : SemilatticeSup β
hf : MonotoneOn f s
hx : x ∈ s
hy : y ∈ s
⊢ f (max x y) = f x ⊔ f y

Tactic:
cases le_total x y <;> have := hf ?_ ?_ ‹_› <;>
    first
    | assumption
    | simp only [*, sup_of_le_left, sup_of_le_right]

Goal state after:
Module: Mathlib.Order.Lattice

Goal state before:
pp: α : Type u
β : Type v
e : α ≃ β
inst✝ : PartialOrder β
⊢ PartialOrder α

Tactic:
let preorder := e.preorder

Goal state after:
α : Type u
β : Type v
e : α ≃ β
inst✝ : PartialOrder β
preorder : Preorder α := e.preorder
⊢ PartialOrder α
Module: Mathlib.Order.Lattice

Goal state before:
pp: α : Type u
β : Type v
e : α ≃ β
inst✝¹ : LinearOrder β
inst✝ : DecidableEq α
max : Max α := e.max
min : Min α := e.min
⊢ LinearOrder α

Tactic:
let preorder := e.preorder

Goal state after:
α : Type u
β : Type v
e : α ≃ β
inst✝¹ : LinearOrder β
inst✝ : DecidableEq α
max : Max α := e.max
min : Min α := e.min
preorder : Preorder α := e.preorder
⊢ LinearOrder α
Module: Mathlib.Order.BooleanAlgebra.Set

Goal state before:
pp: α : Type u_1
x : α
s : Set α
⊢ s ⊆ insert x (s \ {x})

Tactic:
rw [← sdiff_singleton_subset_iff]

Goal state after:
Module: Mathlib.Order.Heyting.Basic

Goal state before:
pp: ι : Type u_1
α : Type u_2
β : Type u_3
inst✝⁶ : Max α
inst✝⁵ : Min α
inst✝⁴ : LE α
inst✝³ : LT α
inst✝² : Bot α
inst✝¹ : SDiff α
inst✝ : GeneralizedCoheytingAlgebra β
f : α → β
hf : Injective f
le : ∀ {x y : α}, f x ≤ f y ↔ x ≤ y
lt : ∀ {x y : α}, f x < f y ↔ x < y
map_sup : ∀ (a b : α), f (a ⊔ b) = f a ⊔ f b
map_inf : ∀ (a b : α), f (a ⊓ b) = f a ⊓ f b
map_bot : f ⊥ = ⊥
map_sdiff : ∀ (a b : α), f (a \ b) = f a \ f b
a b c : α
⊢ f a \ f b ≤ f c ↔ f a ≤ f b ⊔ f c

Tactic:
sdiff_le_iff

Goal state after:
ι : Type u_1
α : Type u_2
β : Type u_3
inst✝⁶ : Max α
inst✝⁵ : Min α
inst✝⁴ : LE α
inst✝³ : LT α
inst✝² : Bot α
inst✝¹ : SDiff α
inst✝ : GeneralizedCoheytingAlgebra β
f : α → β
hf : Injective f
le : ∀ {x y : α}, f x ≤ f y ↔ x ≤ y
lt : ∀ {x y : α}, f x < f y ↔ x < y
map_sup : ∀ (a b : α), f (a ⊔ b) = f a ⊔ f b
map_inf : ∀ (a b : α), f (a ⊓ b) = f a ⊓ f b
map_bot : f ⊥ = ⊥
map_sdiff : ∀ (a b : α), f (a \ b) = f a \ f b
a b c : α
⊢ f a ≤ f b ⊔ f c ↔ f a ≤ f b ⊔ f c
Module: Mathlib.Logic.Equiv.Sum

Goal state before:
pp: α : Sort u_1
α₁ : Sort u_2
α₂ : Sort u_3
β : Sort u_4
β₁ : Sort u_5
β₂ : Sort u_6
γ : Sort u_7
δ : Sort u_8
b : Bool
⊢ Sum.elim (fun x ↦ false) (fun x ↦ true) ((fun b ↦ Bool.casesOn b (inl PUnit.unit) (inr PUnit.unit)) b) = b

Tactic:
cases b <;> rfl

Goal state after:
Module: Mathlib.Order.SymmDiff

Goal state before:
pp: α : Type u_2
inst✝ : GeneralizedCoheytingAlgebra α
a b c : α
⊢ a \ b ≤ c ∧ b \ a ≤ c ↔ a ≤ b ⊔ c ∧ b ≤ a ⊔ c

Tactic:
sdiff_le_iff

Goal state after:
Module: Mathlib.Data.Set.Restrict

Goal state before:
pp: α : Type u_1
β : Type u_2
γ : Type u_3
f : α → β
g : α → γ
g' : β → γ
⊢ range (extend f g g') ⊆ range g ∪ g' '' (range f)ᶜ

Tactic:
rintro _ ⟨y, rfl⟩

Goal state after:
α : Type u_1
β : Type u_2
γ : Type u_3
f : α → β
g : α → γ
g' : β → γ
y : β
⊢ extend f g g' y ∈ range g ∪ g' '' (range f)ᶜ
Module: Mathlib.Data.Set.Prod

Goal state before:
pp: ι : Type u_1
α : ι → Type u_2
β : ι → Type u_3
s : Set ι
f : (i : ι) → α i → β i
hf : ∀ (i : ι), ¬i ∈ s → Surjective (f i)
t : (i : ι) → Set (α i)
⊢ Pi.map f '' s.pi t = s.pi fun i ↦ f i '' t i

Tactic:
refine Subset.antisymm (piMap_image_pi_subset _) fun b hb => ?_

Goal state after:
ι : Type u_1
α : ι → Type u_2
β : ι → Type u_3
s : Set ι
f : (i : ι) → α i → β i
hf : ∀ (i : ι), ¬i ∈ s → Surjective (f i)
t : (i : ι) → Set (α i)
b : (i : ι) → β i
hb : b ∈ s.pi fun i ↦ f i '' t i
⊢ b ∈ Pi.map f '' s.pi t
Module: Mathlib.Data.Set.Prod

Goal state before:
pp: case refine_2.inl
ι : Type u_1
α : ι → Type u_2
s : Set ι
t : (i : ι) → Set (α i)
inst✝ : DecidableEq ι
f : (i : ι) → α i
j : ι
hj hi : j ∈ s
hf : ∀ (j_1 : ι), j_1 ∈ s → j_1 ≠ j → f j_1 ∈ t j_1
x : α j
hx : x ∈ t j
⊢ update f j x j ∈ t j

pp: case refine_2.inr
ι : Type u_1
α : ι → Type u_2
s : Set ι
t : (i : ι) → Set (α i)
i : ι
inst✝ : DecidableEq ι
f : (i : ι) → α i
hi : i ∈ s
hf : ∀ (j : ι), j ∈ s → j ≠ i → f j ∈ t j
x : α i
hx : x ∈ t i
j : ι
hj : j ∈ s
h : j ≠ i
⊢ update f i x j ∈ t j

Tactic:
· simpa

Goal state after:
case refine_2.inr
ι : Type u_1
α : ι → Type u_2
s : Set ι
t : (i : ι) → Set (α i)
i : ι
inst✝ : DecidableEq ι
f : (i : ι) → α i
hi : i ∈ s
hf : ∀ (j : ι), j ∈ s → j ≠ i → f j ∈ t j
x : α i
hx : x ∈ t i
j : ι
hj : j ∈ s
h : j ≠ i
⊢ update f i x j ∈ t j
Module: Mathlib.Data.Set.Function

Goal state before:
pp: α : Type u_1
β : Type u_2
s : Set α
f : α → β
h : InjOn f s
s₁ : Set α
hs₁ : s₁ ∈ 𝒫 s
s₂ : Set α
hs₂ : s₂ ∈ 𝒫 s
h' : f '' s₁ = f '' s₂
⊢ f ⁻¹' f '' s₁ ∩ s = s₂

Tactic:
h',

Goal state after:
α : Type u_1
β : Type u_2
s : Set α
f : α → β
h : InjOn f s
s₁ : Set α
hs₁ : s₁ ∈ 𝒫 s
s₂ : Set α
hs₂ : s₂ ∈ 𝒫 s
h' : f '' s₁ = f '' s₂
⊢ f ⁻¹' f '' s₂ ∩ s = s₂
Module: Mathlib.Data.Set.Prod

Goal state before:
pp: α : Type u_1
β : Type u_2
s : Set α
f : α → β
⊢ Prod.snd '' graphOn f s = f '' s

Tactic:
by ext x; simp

Goal state after:
Module: Mathlib.Data.Set.Function

Goal state before:
pp: α : Type u_1
β : Type u_2
s : Set α
t : Set β
f : α → β
a : α
ha : ¬a ∈ s
hfa : ¬f a ∈ t
h : BijOn f (insert a s) (insert (f a) t)
this : f '' s \ {f a} = t
⊢ ∀ (x : α), x ∈ s → ¬f x = f a

Tactic:
intro x hx

Goal state after:
α : Type u_1
β : Type u_2
s : Set α
t : Set β
f : α → β
a : α
ha : ¬a ∈ s
hfa : ¬f a ∈ t
h : BijOn f (insert a s) (insert (f a) t)
this : f '' s \ {f a} = t
x : α
hx : x ∈ s
⊢ ¬f x = f a
Module: Mathlib.Data.Set.Function

Goal state before:
pp: α : Type u_1
β : Type u_2
s : Set α
f : α → β
f' : β → α
hf : LeftInvOn f' f s
⊢ f' '' f '' s = s

Tactic:
by
  rw [Set.image_image, image_congr hf, image_id']

Goal state after:
Module: Mathlib.Data.Set.Function

Goal state before:
pp: case inl
α : Type u_1
β : Type u_2
n : Nonempty α
f : α → β
hf : Injective f
s : Set α
h : Classical.choice n ∈ s
a : α
⊢ f a ∈ invFun f ⁻¹' s ↔ f a ∈ f '' s ∪ (range f)ᶜ

pp: case inr
α : Type u_1
β : Type u_2
n : Nonempty α
f : α → β
hf : Injective f
s : Set α
h : Classical.choice n ∈ s
x : β
hx : ¬x ∈ range f
⊢ x ∈ invFun f ⁻¹' s ↔ x ∈ f '' s ∪ (range f)ᶜ

Tactic:
· simp only [mem_preimage, mem_union, mem_compl_iff, mem_range_self, not_true, or_false,
      leftInverse_invFun hf _, hf.mem_set_image]

Goal state after:
case inr
α : Type u_1
β : Type u_2
n : Nonempty α
f : α → β
hf : Injective f
s : Set α
h : Classical.choice n ∈ s
x : β
hx : ¬x ∈ range f
⊢ x ∈ invFun f ⁻¹' s ↔ x ∈ f '' s ∪ (range f)ᶜ
Module: Mathlib.Data.Set.Function

Goal state before:
pp: α : Type u_1
β : Type u_2
p : β → Prop
inst✝ : DecidablePred p
f : α ≃ Subtype p
g : Perm α
s t : Set α
h : MapsTo (⇑g) s t
a : α
ha : a ∈ s
⊢ (Subtype.val ∘ ⇑f) (g a) = (g.extendDomain f) ((Subtype.val ∘ ⇑f) a)

Tactic:
simp_rw [Function.comp_apply, extendDomain_apply_image]

Goal state after:
Module: Mathlib.Data.Set.Function

Goal state before:
pp: α : Type u_1
β : Type u_2
p : β → Prop
inst✝ : DecidablePred p
f : α ≃ Subtype p
g : Perm α
s t : Set α
h : SurjOn (⇑g) s t
b : α
hb : b ∈ s
ha : g b ∈ t
⊢ (g.extendDomain f) ((Subtype.val ∘ ⇑f) b) = (Subtype.val ∘ ⇑f) (g b)

Tactic:
simp_rw [Function.comp_apply, extendDomain_apply_image]

Goal state after:
Module: Mathlib.Algebra.Group.Basic

Goal state before:
pp: G : Type u_3
inst✝ : Group G
a b : G
⊢ b⁻¹ = 1 ↔ b = 1

Tactic:
inv_eq_one

Goal state after:
G : Type u_3
inst✝ : Group G
a b : G
⊢ b = 1 ↔ b = 1
Module: Mathlib.Algebra.Group.Units.Defs

Goal state before:
pp: M : Type u_3
inst✝ : Monoid M
u : Mˣ
a : M
x✝ : IsUnit (↑u * a)
v : Mˣ
hv : ↑v = ↑u * a
⊢ IsUnit (↑u⁻¹ * (↑u * a))

Tactic:
exists u⁻¹ * v

Goal state after:
M : Type u_3
inst✝ : Monoid M
u : Mˣ
a : M
x✝ : IsUnit (↑u * a)
v : Mˣ
hv : ↑v = ↑u * a
⊢ ↑(u⁻¹ * v) = ↑u⁻¹ * (↑u * a)
Module: Mathlib.Algebra.Group.Basic

Goal state before:
pp: α✝ : Type u_1
β : Type u_2
G : Type u_3
M : Type u_4
α : Type u_5
s : AddCommMonoid α
n : ℕ
a : α
⊢ (n + 1) • a = n • a + a

Tactic:
change (n + 1) • a = n • a + a

Goal state after:
α✝ : Type u_1
β : Type u_2
G : Type u_3
M : Type u_4
α : Type u_5
s : AddCommMonoid α
n : ℕ
a : α
⊢ (n + 1) • a = n • a + a
Module: Mathlib.Algebra.Group.Units.Basic

Goal state before:
pp: α : Type u
inst✝ : Monoid α
a : α
b : αˣ
⊢ a * ↑b⁻¹ * ↑b = a

Tactic:
rw [mul_assoc, inv_mul, mul_one]

Goal state after:
Module: Mathlib.Algebra.Group.Units.Basic

Goal state before:
pp: α : Type u
inst✝ : CommMonoid α
x y : α
ux uy : αˣ
⊢ x /ₚ ux * (y /ₚ uy) = x * y /ₚ (ux * uy)

Tactic:
by
  rw [divp_mul_eq_mul_divp, ← divp_assoc, divp_divp_eq_divp_mul]

Goal state after:
Module: Mathlib.Control.Basic

Goal state before:
pp: α β γ : Type u
e : Type v
⊢ ∀ {α β : Type u} (x : e ⊕ α) (y : e ⊕ β), x <* y = Function.const β <$> x <*> y

Tactic:
by
    intros
    casesm Sum _ _ <;> rfl

Goal state after:
Module: Mathlib.Control.Basic

Goal state before:
pp: α β γ : Type u
e : Type v
⊢ ∀ {α β : Type u} (f : α → β) (x : e ⊕ α),
    (do
        let a ← x
        pure (f a)) =
      f <$> x

Tactic:
by
    intros
    casesm Sum _ _ <;> rfl

Goal state after:
Module: Mathlib.Control.Basic

Goal state before:
pp: α β γ : Type u
e : Type v
⊢ ∀ {α β : Type u} (f : e ⊕ (α → β)) (x : e ⊕ α),
    (do
        let x_1 ← f
        x_1 <$> x) =
      f <*> x

Tactic:
by
    intros
    casesm Sum _ _ <;> rfl

Goal state after:
Module: Mathlib.Control.Basic

Goal state before:
pp: α β γ : Type u
e : Type v
⊢ ∀ {α β γ : Type u} (x : e ⊕ α) (f : α → e ⊕ β) (g : β → e ⊕ γ), x >>= f >>= g = x >>= fun x ↦ f x >>= g

Tactic:
by
    intros
    casesm Sum _ _ <;> rfl

Goal state after:
Module: Mathlib.Algebra.Group.End

Goal state before:
pp: α : Type u_4
p : α → Prop
inst✝ : DecidablePred p
x y : Perm (Subtype p)
h : ofSubtype x = ofSubtype y
⊢ x = y

Tactic:
rw [Perm.ext_iff] at h ⊢

Goal state after:
α : Type u_4
p : α → Prop
inst✝ : DecidablePred p
x y : Perm (Subtype p)
h : ∀ (x_1 : α), (ofSubtype x) x_1 = (ofSubtype y) x_1
⊢ ∀ (x_1 : Subtype p), x x_1 = y x_1
Module: Mathlib.Algebra.Group.End

Goal state before:
pp: α : Type u_4
p : α → Prop
inst✝ : DecidablePred p
x y : Perm (Subtype p)
h : ∀ (x_1 : α), (ofSubtype x) x_1 = (ofSubtype y) x_1
a : Subtype p
⊢ x a = y a

Tactic:
specialize h a

Goal state after:
α : Type u_4
p : α → Prop
inst✝ : DecidablePred p
x y : Perm (Subtype p)
a : Subtype p
h : (ofSubtype x) ↑a = (ofSubtype y) ↑a
⊢ x a = y a
Module: Mathlib.Algebra.GroupWithZero.Basic

Goal state before:
pp: M₀ : Type u_1
G₀ : Type u_2
inst✝¹ : MonoidWithZero M₀
a✝ : M₀
n✝ : ℕ
inst✝ : NoZeroDivisors M₀
a : M₀
x✝ : IsNilpotent a
n : ℕ
ha : a ^ n = 0
⊢ a = 0

Tactic:
by
    induction n with
    | zero => simpa using congr_arg (a * ·) ha
    | succ n ih => rw [pow_succ, mul_eq_zero] at ha; exact ha.elim ih id

Goal state after:
Module: Mathlib.Algebra.GroupWithZero.Basic

Goal state before:
pp: G₀ : Type u_2
inst✝ : GroupWithZero G₀
a : G₀
⊢ a⁻¹ = 0 ↔ a = 0

Tactic:
inv_eq_iff_eq_inv,

Goal state after:
G₀ : Type u_2
inst✝ : GroupWithZero G₀
a : G₀
⊢ a = 0⁻¹ ↔ a = 0
Module: Mathlib.Algebra.Ring.Basic

Goal state before:
pp: R : Type u_3
inst✝ : NonUnitalNonAssocRing R
r : R
h : ∀ (x : R), r * x = 0 → x = 0
r₁ r₂ : R
eq : (fun x ↦ r * x) r₁ = (fun x ↦ r * x) r₂
⊢ r * (r₁ - r₂) = 0

Tactic:
simp_rw [mul_sub, eq, sub_self]

Goal state after:
Module: Mathlib.Algebra.Ring.Hom.Defs

Goal state before:
pp: F : Type u_1
α : Type u_2
β : Type u_3
γ : Type u_4
inst✝² : CommRing α
inst✝¹ : IsDomain α
inst✝ : CommRing β
f : β →+ α
h : ∀ (x : β), f (x * x) = f x * f x
h_two : 2 ≠ 0
h_one : f 1 = 1
x y : β
⊢ (↑f).toFun (x * y) = (↑f).toFun x * (↑f).toFun y

Tactic:
have hxy := h (x + y)
      rw [mul_add, add_mul, add_mul, f.map_add, f.map_add, f.map_add, f.map_add, h x, h y, add_mul,
        mul_add, mul_add, ← sub_eq_zero, add_comm (f x * f x + f (y * x)), ← sub_sub, ← sub_sub,
        ← sub_sub, mul_comm y x, mul_comm (f y) (f x)] at hxy
      simp only [add_assoc, add_sub_assoc, add_sub_cancel] at hxy
      rw [sub_sub, ← two_mul, ← add_sub_assoc, ← two_mul, ← mul_sub, mul_eq_zero (M₀ := α),
        sub_eq_zero, or_iff_not_imp_left] at hxy
      exact hxy h_two

Goal state after:
Module: Mathlib.Algebra.GroupWithZero.Units.Basic

Goal state before:
pp: G₀ : Type u_3
inst✝ : GroupWithZero G₀
a : G₀
⊢ a = 0 → a / a ≠ 1

Tactic:
simp +contextual

Goal state after:
Module: Mathlib.Algebra.GroupWithZero.Units.Basic

Goal state before:
pp: G₀ : Type u_3
inst✝ : GroupWithZero G₀
a : G₀
ha : a ≠ 0
n : ℕ
⊢ a ^ (1 - ↑n) = a / a ^ n

Tactic:
by
  simpa using zpow_sub₀ ha 1 n

Goal state after:
Module: Mathlib.Algebra.Ring.Parity

Goal state before:
pp: case succ
α : Type u_2
inst✝ : Semiring α
a : α
ha : Odd a
n : ℕ
hrec : Odd (a ^ n)
⊢ Odd (a ^ n * a)

Tactic:
exact hrec.mul ha

Goal state after:
Module: Mathlib.Algebra.Order.Sub.Defs

Goal state before:
pp: α : Type u_1
inst✝⁴ : Preorder α
inst✝³ : AddCommSemigroup α
inst✝² : Sub α
inst✝¹ : OrderedSub α
a b c : α
inst✝ : AddLeftMono α
⊢ b + a - c ≤ b + (a - c)

Tactic:
exact add_tsub_le_assoc

Goal state after:
Module: Mathlib.Algebra.Order.Sub.Defs

Goal state before:
pp: α : Type u_1
inst✝⁴ : Preorder α
inst✝³ : AddCommSemigroup α
inst✝² : Sub α
inst✝¹ : OrderedSub α
a b c d : α
inst✝ : AddLeftMono α
⊢ b - d + a - c ≤ b - d + (a - c)

Tactic:
exact add_tsub_le_assoc

Goal state after:
Module: Mathlib.Algebra.Order.Monoid.Defs

Goal state before:
pp: α : Type u_1
inst✝² : CommMonoid α
inst✝¹ : LinearOrder α
inst✝ : IsOrderedMonoid α
a : α
h : 1 < a * a
⊢ 1 < a

Tactic:
by contrapose! h; exact mul_le_one' h h

Goal state after:
Module: Mathlib.Algebra.Order.GroupWithZero.Basic

Goal state before:
pp: case inl
G₀ : Type u_3
inst✝¹ : GroupWithZero G₀
inst✝ : Preorder G₀
a b : G₀
h : 0 ≤ a / b
⊢ a * 0 / (b * 0) ≤ a / b

pp: case inr
G₀ : Type u_3
inst✝¹ : GroupWithZero G₀
inst✝ : Preorder G₀
a b c : G₀
h : 0 ≤ a / b
hc : c ≠ 0
⊢ a * c / (b * c) ≤ a / b

Tactic:
· simpa

Goal state after:
case inr
G₀ : Type u_3
inst✝¹ : GroupWithZero G₀
inst✝ : Preorder G₀
a b c : G₀
h : 0 ≤ a / b
hc : c ≠ 0
⊢ a * c / (b * c) ≤ a / b
Module: Mathlib.Algebra.Order.GroupWithZero.Basic

Goal state before:
pp: case inl
G₀ : Type u_3
inst✝¹ : GroupWithZero G₀
inst✝ : Preorder G₀
a b : G₀
h : a / b ≤ 0
⊢ a / b ≤ a * 0 / (b * 0)

pp: case inr
G₀ : Type u_3
inst✝¹ : GroupWithZero G₀
inst✝ : Preorder G₀
a b c : G₀
h : a / b ≤ 0
hc : c ≠ 0
⊢ a / b ≤ a * c / (b * c)

Tactic:
· simpa

Goal state after:
case inr
G₀ : Type u_3
inst✝¹ : GroupWithZero G₀
inst✝ : Preorder G₀
a b c : G₀
h : a / b ≤ 0
hc : c ≠ 0
⊢ a / b ≤ a * c / (b * c)
Module: Mathlib.Algebra.Order.Ring.Unbundled.Basic

Goal state before:
pp: R : Type u
inst✝⁶ : Semiring R
inst✝⁵ : LinearOrder R
inst✝⁴ : ExistsAddOfLE R
inst✝³ : PosMulStrictMono R
inst✝² : MulPosStrictMono R
inst✝¹ : AddLeftStrictMono R
inst✝ : AddLeftReflectLT R
a : R
⊢ 0 < a * a ↔ a ≠ 0

Tactic:
by
  constructor
  · rintro h rfl
    rw [mul_zero] at h
    exact h.false
  · intro h
    rcases h.lt_or_gt with h | h
    exacts [mul_pos_of_neg_of_neg h h, mul_pos h h]

Goal state after:
Module: Mathlib.Algebra.Order.GroupWithZero.Basic

Goal state before:
pp: G₀ : Type u_3
inst✝² : GroupWithZero G₀
inst✝¹ : PartialOrder G₀
inst✝ : MulPosReflectLT G₀
a b c : G₀
hc : 0 < c
⊢ b * c⁻¹ < a ↔ b < a * c

Tactic:
mul_inv_lt_iff₀ hc

Goal state after:
G₀ : Type u_3
inst✝² : GroupWithZero G₀
inst✝¹ : PartialOrder G₀
inst✝ : MulPosReflectLT G₀
a b c : G₀
hc : 0 < c
⊢ b < a * c ↔ b < a * c