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stringlengths
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2.09M
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S06_Sequences_and_Convergence.lean
C03S06.convergesTo_unique
[79, 1]
[94, 25]
sorry
s : ℕ → ℝ a b : ℝ sa : ConvergesTo s a sb : ConvergesTo s b abne : ¬a = b ⊢ |a - b| > 0
no goals
Please generate a tactic in lean4 to solve the state. STATE: s : ℕ → ℝ a b : ℝ sa : ConvergesTo s a sb : ConvergesTo s b abne : ¬a = b ⊢ |a - b| > 0 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S06_Sequences_and_Convergence.lean
C03S06.convergesTo_unique
[79, 1]
[94, 25]
change |a - b| / 2 > 0
s : ℕ → ℝ a b : ℝ sa : ConvergesTo s a sb : ConvergesTo s b abne : ¬a = b this : |a - b| > 0 ε : ℝ := |a - b| / 2 ⊢ ε > 0
s : ℕ → ℝ a b : ℝ sa : ConvergesTo s a sb : ConvergesTo s b abne : ¬a = b this : |a - b| > 0 ε : ℝ := |a - b| / 2 ⊢ |a - b| / 2 > 0
Please generate a tactic in lean4 to solve the state. STATE: s : ℕ → ℝ a b : ℝ sa : ConvergesTo s a sb : ConvergesTo s b abne : ¬a = b this : |a - b| > 0 ε : ℝ := |a - b| / 2 ⊢ ε > 0 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S06_Sequences_and_Convergence.lean
C03S06.convergesTo_unique
[79, 1]
[94, 25]
linarith
s : ℕ → ℝ a b : ℝ sa : ConvergesTo s a sb : ConvergesTo s b abne : ¬a = b this : |a - b| > 0 ε : ℝ := |a - b| / 2 ⊢ |a - b| / 2 > 0
no goals
Please generate a tactic in lean4 to solve the state. STATE: s : ℕ → ℝ a b : ℝ sa : ConvergesTo s a sb : ConvergesTo s b abne : ¬a = b this : |a - b| > 0 ε : ℝ := |a - b| / 2 ⊢ |a - b| / 2 > 0 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S06_Sequences_and_Convergence.lean
C03S06.convergesTo_unique
[79, 1]
[94, 25]
sorry
s : ℕ → ℝ a b : ℝ sa : ConvergesTo s a sb : ConvergesTo s b abne : ¬a = b this : |a - b| > 0 ε : ℝ := |a - b| / 2 εpos : ε > 0 Na : ℕ hNa : ∀ n ≥ Na, |s n - a| < ε Nb : ℕ hNb : ∀ n ≥ Nb, |s n - b| < ε N : ℕ := max Na Nb ⊢ |s N - a| < ε
no goals
Please generate a tactic in lean4 to solve the state. STATE: s : ℕ → ℝ a b : ℝ sa : ConvergesTo s a sb : ConvergesTo s b abne : ¬a = b this : |a - b| > 0 ε : ℝ := |a - b| / 2 εpos : ε > 0 Na : ℕ hNa : ∀ n ≥ Na, |s n - a| < ε Nb : ℕ hNb : ∀ n ≥ Nb, |s n - b| < ε N : ℕ := max Na Nb ⊢ |s N - a| < ε TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S06_Sequences_and_Convergence.lean
C03S06.convergesTo_unique
[79, 1]
[94, 25]
sorry
s : ℕ → ℝ a b : ℝ sa : ConvergesTo s a sb : ConvergesTo s b abne : ¬a = b this : |a - b| > 0 ε : ℝ := |a - b| / 2 εpos : ε > 0 Na : ℕ hNa : ∀ n ≥ Na, |s n - a| < ε Nb : ℕ hNb : ∀ n ≥ Nb, |s n - b| < ε N : ℕ := max Na Nb absa : |s N - a| < ε ⊢ |s N - b| < ε
no goals
Please generate a tactic in lean4 to solve the state. STATE: s : ℕ → ℝ a b : ℝ sa : ConvergesTo s a sb : ConvergesTo s b abne : ¬a = b this : |a - b| > 0 ε : ℝ := |a - b| / 2 εpos : ε > 0 Na : ℕ hNa : ∀ n ≥ Na, |s n - a| < ε Nb : ℕ hNb : ∀ n ≥ Nb, |s n - b| < ε N : ℕ := max Na Nb absa : |s N - a| < ε ⊢ |s N - b| < ε TA...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S06_Sequences_and_Convergence.lean
C03S06.convergesTo_unique
[79, 1]
[94, 25]
sorry
s : ℕ → ℝ a b : ℝ sa : ConvergesTo s a sb : ConvergesTo s b abne : ¬a = b this : |a - b| > 0 ε : ℝ := |a - b| / 2 εpos : ε > 0 Na : ℕ hNa : ∀ n ≥ Na, |s n - a| < ε Nb : ℕ hNb : ∀ n ≥ Nb, |s n - b| < ε N : ℕ := max Na Nb absa : |s N - a| < ε absb : |s N - b| < ε ⊢ |a - b| < |a - b|
no goals
Please generate a tactic in lean4 to solve the state. STATE: s : ℕ → ℝ a b : ℝ sa : ConvergesTo s a sb : ConvergesTo s b abne : ¬a = b this : |a - b| > 0 ε : ℝ := |a - b| / 2 εpos : ε > 0 Na : ℕ hNa : ∀ n ≥ Na, |s n - a| < ε Nb : ℕ hNb : ∀ n ≥ Nb, |s n - b| < ε N : ℕ := max Na Nb absa : |s N - a| < ε absb : |s N - b| <...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S04_Conjunction_and_Iff.lean
C03S04.aux
[107, 1]
[109, 17]
sorry
x y : ℝ h : x ^ 2 + y ^ 2 = 0 ⊢ x ^ 2 = 0
no goals
Please generate a tactic in lean4 to solve the state. STATE: x y : ℝ h : x ^ 2 + y ^ 2 = 0 ⊢ x ^ 2 = 0 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S04_Conjunction_and_Iff.lean
C03S04.not_monotone_iff
[127, 1]
[130, 6]
rw [Monotone]
f : ℝ → ℝ ⊢ ¬Monotone f ↔ ∃ x y, x ≤ y ∧ f x > f y
f : ℝ → ℝ ⊢ (¬∀ ⦃a b : ℝ⦄, a ≤ b → f a ≤ f b) ↔ ∃ x y, x ≤ y ∧ f x > f y
Please generate a tactic in lean4 to solve the state. STATE: f : ℝ → ℝ ⊢ ¬Monotone f ↔ ∃ x y, x ≤ y ∧ f x > f y TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S04_Conjunction_and_Iff.lean
C03S04.not_monotone_iff
[127, 1]
[130, 6]
push_neg
f : ℝ → ℝ ⊢ (¬∀ ⦃a b : ℝ⦄, a ≤ b → f a ≤ f b) ↔ ∃ x y, x ≤ y ∧ f x > f y
f : ℝ → ℝ ⊢ (∃ a b, a ≤ b ∧ f b < f a) ↔ ∃ x y, x ≤ y ∧ f x > f y
Please generate a tactic in lean4 to solve the state. STATE: f : ℝ → ℝ ⊢ (¬∀ ⦃a b : ℝ⦄, a ≤ b → f a ≤ f b) ↔ ∃ x y, x ≤ y ∧ f x > f y TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S04_Conjunction_and_Iff.lean
C03S04.not_monotone_iff
[127, 1]
[130, 6]
rfl
f : ℝ → ℝ ⊢ (∃ a b, a ≤ b ∧ f b < f a) ↔ ∃ x y, x ≤ y ∧ f x > f y
no goals
Please generate a tactic in lean4 to solve the state. STATE: f : ℝ → ℝ ⊢ (∃ a b, a ≤ b ∧ f b < f a) ↔ ∃ x y, x ≤ y ∧ f x > f y TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/S05_Proving_Facts_about_Algebraic_Structures.lean
absorb1
[48, 1]
[49, 8]
sorry
α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊓ (x ⊔ y) = x
no goals
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊓ (x ⊔ y) = x TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/S05_Proving_Facts_about_Algebraic_Structures.lean
absorb2
[51, 1]
[52, 8]
sorry
α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊔ x ⊓ y = x
no goals
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊔ x ⊓ y = x TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.add_neg_cancel_right
[8, 1]
[9, 42]
rw [add_assoc, add_right_neg, add_zero]
R : Type u_1 inst✝ : Ring R a b : R ⊢ a + b + -b = a
no goals
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : Ring R a b : R ⊢ a + b + -b = a TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.add_left_cancel
[11, 1]
[12, 57]
rw [← neg_add_cancel_left a b, h, neg_add_cancel_left]
R : Type u_1 inst✝ : Ring R a b c : R h : a + b = a + c ⊢ b = c
no goals
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : Ring R a b c : R h : a + b = a + c ⊢ b = c TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.add_right_cancel
[14, 1]
[15, 59]
rw [← add_neg_cancel_right a b, h, add_neg_cancel_right]
R : Type u_1 inst✝ : Ring R a b c : R h : a + b = c + b ⊢ a = c
no goals
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : Ring R a b c : R h : a + b = c + b ⊢ a = c TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.zero_mul
[17, 1]
[19, 25]
have h : 0 * a + 0 * a = 0 * a + 0 := by rw [← add_mul, add_zero, add_zero]
R : Type u_1 inst✝ : Ring R a : R ⊢ 0 * a = 0
R : Type u_1 inst✝ : Ring R a : R h : 0 * a + 0 * a = 0 * a + 0 ⊢ 0 * a = 0
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : Ring R a : R ⊢ 0 * a = 0 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.zero_mul
[17, 1]
[19, 25]
rw [add_left_cancel h]
R : Type u_1 inst✝ : Ring R a : R h : 0 * a + 0 * a = 0 * a + 0 ⊢ 0 * a = 0
no goals
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : Ring R a : R h : 0 * a + 0 * a = 0 * a + 0 ⊢ 0 * a = 0 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.zero_mul
[17, 1]
[19, 25]
rw [← add_mul, add_zero, add_zero]
R : Type u_1 inst✝ : Ring R a : R ⊢ 0 * a + 0 * a = 0 * a + 0
no goals
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : Ring R a : R ⊢ 0 * a + 0 * a = 0 * a + 0 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.neg_eq_of_add_eq_zero
[21, 1]
[22, 46]
rw [← neg_add_cancel_left a b, h, add_zero]
R : Type u_1 inst✝ : Ring R a b : R h : a + b = 0 ⊢ -a = b
no goals
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : Ring R a b : R h : a + b = 0 ⊢ -a = b TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.eq_neg_of_add_eq_zero
[24, 1]
[27, 19]
symm
R : Type u_1 inst✝ : Ring R a b : R h : a + b = 0 ⊢ a = -b
R : Type u_1 inst✝ : Ring R a b : R h : a + b = 0 ⊢ -b = a
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : Ring R a b : R h : a + b = 0 ⊢ a = -b TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.eq_neg_of_add_eq_zero
[24, 1]
[27, 19]
apply neg_eq_of_add_eq_zero
R : Type u_1 inst✝ : Ring R a b : R h : a + b = 0 ⊢ -b = a
case h R : Type u_1 inst✝ : Ring R a b : R h : a + b = 0 ⊢ b + a = 0
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : Ring R a b : R h : a + b = 0 ⊢ -b = a TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.eq_neg_of_add_eq_zero
[24, 1]
[27, 19]
rw [add_comm, h]
case h R : Type u_1 inst✝ : Ring R a b : R h : a + b = 0 ⊢ b + a = 0
no goals
Please generate a tactic in lean4 to solve the state. STATE: case h R : Type u_1 inst✝ : Ring R a b : R h : a + b = 0 ⊢ b + a = 0 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.neg_zero
[29, 1]
[31, 16]
apply neg_eq_of_add_eq_zero
R : Type u_1 inst✝ : Ring R ⊢ -0 = 0
case h R : Type u_1 inst✝ : Ring R ⊢ 0 + 0 = 0
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : Ring R ⊢ -0 = 0 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.neg_zero
[29, 1]
[31, 16]
rw [add_zero]
case h R : Type u_1 inst✝ : Ring R ⊢ 0 + 0 = 0
no goals
Please generate a tactic in lean4 to solve the state. STATE: case h R : Type u_1 inst✝ : Ring R ⊢ 0 + 0 = 0 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.neg_neg
[33, 1]
[35, 20]
apply neg_eq_of_add_eq_zero
R : Type u_1 inst✝ : Ring R a : R ⊢ - -a = a
case h R : Type u_1 inst✝ : Ring R a : R ⊢ -a + a = 0
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : Ring R a : R ⊢ - -a = a TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.neg_neg
[33, 1]
[35, 20]
rw [add_left_neg]
case h R : Type u_1 inst✝ : Ring R a : R ⊢ -a + a = 0
no goals
Please generate a tactic in lean4 to solve the state. STATE: case h R : Type u_1 inst✝ : Ring R a : R ⊢ -a + a = 0 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.self_sub
[42, 1]
[43, 37]
rw [sub_eq_add_neg, add_right_neg]
R : Type u_1 inst✝ : Ring R a : R ⊢ a - a = 0
no goals
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : Ring R a : R ⊢ a - a = 0 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.one_add_one_eq_two
[45, 1]
[46, 11]
norm_num
R : Type u_1 inst✝ : Ring R ⊢ 1 + 1 = 2
no goals
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : Ring R ⊢ 1 + 1 = 2 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyRing.two_mul
[48, 1]
[49, 46]
rw [← one_add_one_eq_two, add_mul, one_mul]
R : Type u_1 inst✝ : Ring R a : R ⊢ 2 * a = a + a
no goals
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : Ring R a : R ⊢ 2 * a = a + a TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyGroup.mul_right_inv
[58, 1]
[61, 47]
have h : (a * a⁻¹)⁻¹ * (a * a⁻¹ * (a * a⁻¹)) = 1 := by rw [mul_assoc, ← mul_assoc a⁻¹ a, mul_left_inv, one_mul, mul_left_inv]
G : Type u_1 inst✝ : Group G a : G ⊢ a * a⁻¹ = 1
G : Type u_1 inst✝ : Group G a : G h : (a * a⁻¹)⁻¹ * (a * a⁻¹ * (a * a⁻¹)) = 1 ⊢ a * a⁻¹ = 1
Please generate a tactic in lean4 to solve the state. STATE: G : Type u_1 inst✝ : Group G a : G ⊢ a * a⁻¹ = 1 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyGroup.mul_right_inv
[58, 1]
[61, 47]
rw [← h, ← mul_assoc, mul_left_inv, one_mul]
G : Type u_1 inst✝ : Group G a : G h : (a * a⁻¹)⁻¹ * (a * a⁻¹ * (a * a⁻¹)) = 1 ⊢ a * a⁻¹ = 1
no goals
Please generate a tactic in lean4 to solve the state. STATE: G : Type u_1 inst✝ : Group G a : G h : (a * a⁻¹)⁻¹ * (a * a⁻¹ * (a * a⁻¹)) = 1 ⊢ a * a⁻¹ = 1 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyGroup.mul_right_inv
[58, 1]
[61, 47]
rw [mul_assoc, ← mul_assoc a⁻¹ a, mul_left_inv, one_mul, mul_left_inv]
G : Type u_1 inst✝ : Group G a : G ⊢ (a * a⁻¹)⁻¹ * (a * a⁻¹ * (a * a⁻¹)) = 1
no goals
Please generate a tactic in lean4 to solve the state. STATE: G : Type u_1 inst✝ : Group G a : G ⊢ (a * a⁻¹)⁻¹ * (a * a⁻¹ * (a * a⁻¹)) = 1 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyGroup.mul_one
[63, 1]
[64, 61]
rw [← mul_left_inv a, ← mul_assoc, mul_right_inv, one_mul]
G : Type u_1 inst✝ : Group G a : G ⊢ a * 1 = a
no goals
Please generate a tactic in lean4 to solve the state. STATE: G : Type u_1 inst✝ : Group G a : G ⊢ a * 1 = a TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S02_Proving_Identities_in_Algebraic_Structures.lean
MyGroup.mul_inv_rev
[66, 1]
[68, 52]
rw [← one_mul (b⁻¹ * a⁻¹), ← mul_left_inv (a * b), mul_assoc, mul_assoc, ← mul_assoc b b⁻¹, mul_right_inv, one_mul, mul_right_inv, mul_one]
G : Type u_1 inst✝ : Group G a b : G ⊢ (a * b)⁻¹ = b⁻¹ * a⁻¹
no goals
Please generate a tactic in lean4 to solve the state. STATE: G : Type u_1 inst✝ : Group G a b : G ⊢ (a * b)⁻¹ = b⁻¹ * a⁻¹ TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S03_Using_Theorems_and_Lemmas.lean
fact1
[38, 1]
[43, 11]
have h : 0 ≤ a ^ 2 - 2 * a * b + b ^ 2
a b c d e : ℝ ⊢ a * b * 2 ≤ a ^ 2 + b ^ 2
case h a b c d e : ℝ ⊢ 0 ≤ a ^ 2 - 2 * a * b + b ^ 2 a b c d e : ℝ h : 0 ≤ a ^ 2 - 2 * a * b + b ^ 2 ⊢ a * b * 2 ≤ a ^ 2 + b ^ 2
Please generate a tactic in lean4 to solve the state. STATE: a b c d e : ℝ ⊢ a * b * 2 ≤ a ^ 2 + b ^ 2 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S03_Using_Theorems_and_Lemmas.lean
fact1
[38, 1]
[43, 11]
calc a ^ 2 - 2 * a * b + b ^ 2 = (a - b) ^ 2 := by ring _ ≥ 0 := by apply pow_two_nonneg
case h a b c d e : ℝ ⊢ 0 ≤ a ^ 2 - 2 * a * b + b ^ 2 a b c d e : ℝ h : 0 ≤ a ^ 2 - 2 * a * b + b ^ 2 ⊢ a * b * 2 ≤ a ^ 2 + b ^ 2
a b c d e : ℝ h : 0 ≤ a ^ 2 - 2 * a * b + b ^ 2 ⊢ a * b * 2 ≤ a ^ 2 + b ^ 2
Please generate a tactic in lean4 to solve the state. STATE: case h a b c d e : ℝ ⊢ 0 ≤ a ^ 2 - 2 * a * b + b ^ 2 a b c d e : ℝ h : 0 ≤ a ^ 2 - 2 * a * b + b ^ 2 ⊢ a * b * 2 ≤ a ^ 2 + b ^ 2 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S03_Using_Theorems_and_Lemmas.lean
fact1
[38, 1]
[43, 11]
linarith
a b c d e : ℝ h : 0 ≤ a ^ 2 - 2 * a * b + b ^ 2 ⊢ a * b * 2 ≤ a ^ 2 + b ^ 2
no goals
Please generate a tactic in lean4 to solve the state. STATE: a b c d e : ℝ h : 0 ≤ a ^ 2 - 2 * a * b + b ^ 2 ⊢ a * b * 2 ≤ a ^ 2 + b ^ 2 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S03_Using_Theorems_and_Lemmas.lean
fact1
[38, 1]
[43, 11]
ring
a b c d e : ℝ ⊢ a ^ 2 - 2 * a * b + b ^ 2 = (a - b) ^ 2
no goals
Please generate a tactic in lean4 to solve the state. STATE: a b c d e : ℝ ⊢ a ^ 2 - 2 * a * b + b ^ 2 = (a - b) ^ 2 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S03_Using_Theorems_and_Lemmas.lean
fact1
[38, 1]
[43, 11]
apply pow_two_nonneg
a b c d e : ℝ ⊢ (a - b) ^ 2 ≥ 0
no goals
Please generate a tactic in lean4 to solve the state. STATE: a b c d e : ℝ ⊢ (a - b) ^ 2 ≥ 0 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S03_Using_Theorems_and_Lemmas.lean
fact2
[45, 1]
[50, 11]
have h : 0 ≤ a ^ 2 + 2 * a * b + b ^ 2
a b c d e : ℝ ⊢ -(a * b) * 2 ≤ a ^ 2 + b ^ 2
case h a b c d e : ℝ ⊢ 0 ≤ a ^ 2 + 2 * a * b + b ^ 2 a b c d e : ℝ h : 0 ≤ a ^ 2 + 2 * a * b + b ^ 2 ⊢ -(a * b) * 2 ≤ a ^ 2 + b ^ 2
Please generate a tactic in lean4 to solve the state. STATE: a b c d e : ℝ ⊢ -(a * b) * 2 ≤ a ^ 2 + b ^ 2 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S03_Using_Theorems_and_Lemmas.lean
fact2
[45, 1]
[50, 11]
calc a ^ 2 + 2 * a * b + b ^ 2 = (a + b) ^ 2 := by ring _ ≥ 0 := by apply pow_two_nonneg
case h a b c d e : ℝ ⊢ 0 ≤ a ^ 2 + 2 * a * b + b ^ 2 a b c d e : ℝ h : 0 ≤ a ^ 2 + 2 * a * b + b ^ 2 ⊢ -(a * b) * 2 ≤ a ^ 2 + b ^ 2
a b c d e : ℝ h : 0 ≤ a ^ 2 + 2 * a * b + b ^ 2 ⊢ -(a * b) * 2 ≤ a ^ 2 + b ^ 2
Please generate a tactic in lean4 to solve the state. STATE: case h a b c d e : ℝ ⊢ 0 ≤ a ^ 2 + 2 * a * b + b ^ 2 a b c d e : ℝ h : 0 ≤ a ^ 2 + 2 * a * b + b ^ 2 ⊢ -(a * b) * 2 ≤ a ^ 2 + b ^ 2 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S03_Using_Theorems_and_Lemmas.lean
fact2
[45, 1]
[50, 11]
linarith
a b c d e : ℝ h : 0 ≤ a ^ 2 + 2 * a * b + b ^ 2 ⊢ -(a * b) * 2 ≤ a ^ 2 + b ^ 2
no goals
Please generate a tactic in lean4 to solve the state. STATE: a b c d e : ℝ h : 0 ≤ a ^ 2 + 2 * a * b + b ^ 2 ⊢ -(a * b) * 2 ≤ a ^ 2 + b ^ 2 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S03_Using_Theorems_and_Lemmas.lean
fact2
[45, 1]
[50, 11]
ring
a b c d e : ℝ ⊢ a ^ 2 + 2 * a * b + b ^ 2 = (a + b) ^ 2
no goals
Please generate a tactic in lean4 to solve the state. STATE: a b c d e : ℝ ⊢ a ^ 2 + 2 * a * b + b ^ 2 = (a + b) ^ 2 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S03_Using_Theorems_and_Lemmas.lean
fact2
[45, 1]
[50, 11]
apply pow_two_nonneg
a b c d e : ℝ ⊢ (a + b) ^ 2 ≥ 0
no goals
Please generate a tactic in lean4 to solve the state. STATE: a b c d e : ℝ ⊢ (a + b) ^ 2 ≥ 0 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/S04_More_on_Order_and_Divisibility.lean
C02S04.aux
[45, 1]
[46, 8]
sorry
a b c d : ℝ ⊢ min a b + c ≤ min (a + c) (b + c)
no goals
Please generate a tactic in lean4 to solve the state. STATE: a b c d : ℝ ⊢ min a b + c ≤ min (a + c) (b + c) TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S05_Proving_Facts_about_Algebraic_Structures.lean
absorb1
[64, 1]
[69, 20]
apply le_antisymm
α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊓ (x ⊔ y) = x
case a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊓ (x ⊔ y) ≤ x case a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ≤ x ⊓ (x ⊔ y)
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊓ (x ⊔ y) = x TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S05_Proving_Facts_about_Algebraic_Structures.lean
absorb1
[64, 1]
[69, 20]
apply le_inf
case a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ≤ x ⊓ (x ⊔ y)
case a.a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ≤ x case a.a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ≤ x ⊔ y
Please generate a tactic in lean4 to solve the state. STATE: case a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ≤ x ⊓ (x ⊔ y) TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S05_Proving_Facts_about_Algebraic_Structures.lean
absorb1
[64, 1]
[69, 20]
apply le_sup_left
case a.a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ≤ x ⊔ y
no goals
Please generate a tactic in lean4 to solve the state. STATE: case a.a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ≤ x ⊔ y TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S05_Proving_Facts_about_Algebraic_Structures.lean
absorb1
[64, 1]
[69, 20]
apply inf_le_left
case a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊓ (x ⊔ y) ≤ x
no goals
Please generate a tactic in lean4 to solve the state. STATE: case a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊓ (x ⊔ y) ≤ x TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S05_Proving_Facts_about_Algebraic_Structures.lean
absorb1
[64, 1]
[69, 20]
apply le_refl
case a.a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ≤ x
no goals
Please generate a tactic in lean4 to solve the state. STATE: case a.a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ≤ x TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S05_Proving_Facts_about_Algebraic_Structures.lean
absorb2
[71, 1]
[76, 20]
apply le_antisymm
α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊔ x ⊓ y = x
case a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊔ x ⊓ y ≤ x case a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ≤ x ⊔ x ⊓ y
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊔ x ⊓ y = x TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S05_Proving_Facts_about_Algebraic_Structures.lean
absorb2
[71, 1]
[76, 20]
apply le_sup_left
case a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ≤ x ⊔ x ⊓ y
no goals
Please generate a tactic in lean4 to solve the state. STATE: case a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ≤ x ⊔ x ⊓ y TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S05_Proving_Facts_about_Algebraic_Structures.lean
absorb2
[71, 1]
[76, 20]
apply sup_le
case a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊔ x ⊓ y ≤ x
case a.a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ≤ x case a.a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊓ y ≤ x
Please generate a tactic in lean4 to solve the state. STATE: case a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊔ x ⊓ y ≤ x TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S05_Proving_Facts_about_Algebraic_Structures.lean
absorb2
[71, 1]
[76, 20]
apply inf_le_left
case a.a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊓ y ≤ x
no goals
Please generate a tactic in lean4 to solve the state. STATE: case a.a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ⊓ y ≤ x TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S05_Proving_Facts_about_Algebraic_Structures.lean
absorb2
[71, 1]
[76, 20]
apply le_refl
case a.a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ≤ x
no goals
Please generate a tactic in lean4 to solve the state. STATE: case a.a α : Type u_1 inst✝ : Lattice α x y z : α ⊢ x ≤ x TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S05_Proving_Facts_about_Algebraic_Structures.lean
aux1
[108, 1]
[110, 26]
rw [← sub_self a, sub_eq_add_neg, sub_eq_add_neg, add_comm, add_comm b]
R : Type u_1 inst✝ : StrictOrderedRing R a b c : R h : a ≤ b ⊢ 0 ≤ b - a
R : Type u_1 inst✝ : StrictOrderedRing R a b c : R h : a ≤ b ⊢ -a + a ≤ -a + b
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : StrictOrderedRing R a b c : R h : a ≤ b ⊢ 0 ≤ b - a TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S05_Proving_Facts_about_Algebraic_Structures.lean
aux1
[108, 1]
[110, 26]
apply add_le_add_left h
R : Type u_1 inst✝ : StrictOrderedRing R a b c : R h : a ≤ b ⊢ -a + a ≤ -a + b
no goals
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : StrictOrderedRing R a b c : R h : a ≤ b ⊢ -a + a ≤ -a + b TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S05_Proving_Facts_about_Algebraic_Structures.lean
aux2
[112, 1]
[114, 26]
rw [← add_zero a, ← sub_add_cancel b a, add_comm (b - a)]
R : Type u_1 inst✝ : StrictOrderedRing R a b c : R h : 0 ≤ b - a ⊢ a ≤ b
R : Type u_1 inst✝ : StrictOrderedRing R a b c : R h : 0 ≤ b - a ⊢ a + 0 ≤ a + (b - a)
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : StrictOrderedRing R a b c : R h : 0 ≤ b - a ⊢ a ≤ b TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S2_Basics/solutions/Solutions_S05_Proving_Facts_about_Algebraic_Structures.lean
aux2
[112, 1]
[114, 26]
apply add_le_add_left h
R : Type u_1 inst✝ : StrictOrderedRing R a b c : R h : 0 ≤ b - a ⊢ a + 0 ≤ a + (b - a)
no goals
Please generate a tactic in lean4 to solve the state. STATE: R : Type u_1 inst✝ : StrictOrderedRing R a b c : R h : 0 ≤ b - a ⊢ a + 0 ≤ a + (b - a) TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S02_The_Existential_Quantifier.lean
C03S02.sumOfSquares_mul
[105, 1]
[111, 7]
rcases sosx with ⟨a, b, xeq⟩
α : Type u_1 inst✝ : CommRing α x y : α sosx : SumOfSquares x sosy : SumOfSquares y ⊢ SumOfSquares (x * y)
case intro.intro α : Type u_1 inst✝ : CommRing α x y : α sosy : SumOfSquares y a b : α xeq : x = a ^ 2 + b ^ 2 ⊢ SumOfSquares (x * y)
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 inst✝ : CommRing α x y : α sosx : SumOfSquares x sosy : SumOfSquares y ⊢ SumOfSquares (x * y) TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S02_The_Existential_Quantifier.lean
C03S02.sumOfSquares_mul
[105, 1]
[111, 7]
rcases sosy with ⟨c, d, yeq⟩
case intro.intro α : Type u_1 inst✝ : CommRing α x y : α sosy : SumOfSquares y a b : α xeq : x = a ^ 2 + b ^ 2 ⊢ SumOfSquares (x * y)
case intro.intro.intro.intro α : Type u_1 inst✝ : CommRing α x y a b : α xeq : x = a ^ 2 + b ^ 2 c d : α yeq : y = c ^ 2 + d ^ 2 ⊢ SumOfSquares (x * y)
Please generate a tactic in lean4 to solve the state. STATE: case intro.intro α : Type u_1 inst✝ : CommRing α x y : α sosy : SumOfSquares y a b : α xeq : x = a ^ 2 + b ^ 2 ⊢ SumOfSquares (x * y) TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S02_The_Existential_Quantifier.lean
C03S02.sumOfSquares_mul
[105, 1]
[111, 7]
rw [xeq, yeq]
case intro.intro.intro.intro α : Type u_1 inst✝ : CommRing α x y a b : α xeq : x = a ^ 2 + b ^ 2 c d : α yeq : y = c ^ 2 + d ^ 2 ⊢ SumOfSquares (x * y)
case intro.intro.intro.intro α : Type u_1 inst✝ : CommRing α x y a b : α xeq : x = a ^ 2 + b ^ 2 c d : α yeq : y = c ^ 2 + d ^ 2 ⊢ SumOfSquares ((a ^ 2 + b ^ 2) * (c ^ 2 + d ^ 2))
Please generate a tactic in lean4 to solve the state. STATE: case intro.intro.intro.intro α : Type u_1 inst✝ : CommRing α x y a b : α xeq : x = a ^ 2 + b ^ 2 c d : α yeq : y = c ^ 2 + d ^ 2 ⊢ SumOfSquares (x * y) TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S02_The_Existential_Quantifier.lean
C03S02.sumOfSquares_mul
[105, 1]
[111, 7]
use a * c - b * d, a * d + b * c
case intro.intro.intro.intro α : Type u_1 inst✝ : CommRing α x y a b : α xeq : x = a ^ 2 + b ^ 2 c d : α yeq : y = c ^ 2 + d ^ 2 ⊢ SumOfSquares ((a ^ 2 + b ^ 2) * (c ^ 2 + d ^ 2))
case h α : Type u_1 inst✝ : CommRing α x y a b : α xeq : x = a ^ 2 + b ^ 2 c d : α yeq : y = c ^ 2 + d ^ 2 ⊢ (a ^ 2 + b ^ 2) * (c ^ 2 + d ^ 2) = (a * c - b * d) ^ 2 + (a * d + b * c) ^ 2
Please generate a tactic in lean4 to solve the state. STATE: case intro.intro.intro.intro α : Type u_1 inst✝ : CommRing α x y a b : α xeq : x = a ^ 2 + b ^ 2 c d : α yeq : y = c ^ 2 + d ^ 2 ⊢ SumOfSquares ((a ^ 2 + b ^ 2) * (c ^ 2 + d ^ 2)) TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S02_The_Existential_Quantifier.lean
C03S02.sumOfSquares_mul
[105, 1]
[111, 7]
ring
case h α : Type u_1 inst✝ : CommRing α x y a b : α xeq : x = a ^ 2 + b ^ 2 c d : α yeq : y = c ^ 2 + d ^ 2 ⊢ (a ^ 2 + b ^ 2) * (c ^ 2 + d ^ 2) = (a * c - b * d) ^ 2 + (a * d + b * c) ^ 2
no goals
Please generate a tactic in lean4 to solve the state. STATE: case h α : Type u_1 inst✝ : CommRing α x y a b : α xeq : x = a ^ 2 + b ^ 2 c d : α yeq : y = c ^ 2 + d ^ 2 ⊢ (a ^ 2 + b ^ 2) * (c ^ 2 + d ^ 2) = (a * c - b * d) ^ 2 + (a * d + b * c) ^ 2 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S02_The_Existential_Quantifier.lean
C03S02.sumOfSquares_mul'
[113, 1]
[118, 7]
rcases sosx with ⟨a, b, rfl⟩
α : Type u_1 inst✝ : CommRing α x y : α sosx : SumOfSquares x sosy : SumOfSquares y ⊢ SumOfSquares (x * y)
case intro.intro α : Type u_1 inst✝ : CommRing α y : α sosy : SumOfSquares y a b : α ⊢ SumOfSquares ((a ^ 2 + b ^ 2) * y)
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 inst✝ : CommRing α x y : α sosx : SumOfSquares x sosy : SumOfSquares y ⊢ SumOfSquares (x * y) TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S02_The_Existential_Quantifier.lean
C03S02.sumOfSquares_mul'
[113, 1]
[118, 7]
rcases sosy with ⟨c, d, rfl⟩
case intro.intro α : Type u_1 inst✝ : CommRing α y : α sosy : SumOfSquares y a b : α ⊢ SumOfSquares ((a ^ 2 + b ^ 2) * y)
case intro.intro.intro.intro α : Type u_1 inst✝ : CommRing α a b c d : α ⊢ SumOfSquares ((a ^ 2 + b ^ 2) * (c ^ 2 + d ^ 2))
Please generate a tactic in lean4 to solve the state. STATE: case intro.intro α : Type u_1 inst✝ : CommRing α y : α sosy : SumOfSquares y a b : α ⊢ SumOfSquares ((a ^ 2 + b ^ 2) * y) TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S02_The_Existential_Quantifier.lean
C03S02.sumOfSquares_mul'
[113, 1]
[118, 7]
use a * c - b * d, a * d + b * c
case intro.intro.intro.intro α : Type u_1 inst✝ : CommRing α a b c d : α ⊢ SumOfSquares ((a ^ 2 + b ^ 2) * (c ^ 2 + d ^ 2))
case h α : Type u_1 inst✝ : CommRing α a b c d : α ⊢ (a ^ 2 + b ^ 2) * (c ^ 2 + d ^ 2) = (a * c - b * d) ^ 2 + (a * d + b * c) ^ 2
Please generate a tactic in lean4 to solve the state. STATE: case intro.intro.intro.intro α : Type u_1 inst✝ : CommRing α a b c d : α ⊢ SumOfSquares ((a ^ 2 + b ^ 2) * (c ^ 2 + d ^ 2)) TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S3_Logic/S02_The_Existential_Quantifier.lean
C03S02.sumOfSquares_mul'
[113, 1]
[118, 7]
ring
case h α : Type u_1 inst✝ : CommRing α a b c d : α ⊢ (a ^ 2 + b ^ 2) * (c ^ 2 + d ^ 2) = (a * c - b * d) ^ 2 + (a * d + b * c) ^ 2
no goals
Please generate a tactic in lean4 to solve the state. STATE: case h α : Type u_1 inst✝ : CommRing α a b c d : α ⊢ (a ^ 2 + b ^ 2) * (c ^ 2 + d ^ 2) = (a * c - b * d) ^ 2 + (a * d + b * c) ^ 2 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_right_inv
[25, 1]
[35, 23]
have : x ∈ g '' univ := by contrapose! hx rw [sbSet, mem_iUnion] use 0 rw [sbAux, mem_diff] exact ⟨mem_univ _, hx⟩
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ sbSet f g ⊢ g (invFun g x) = x
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ sbSet f g this : x ∈ g '' univ ⊢ g (invFun g x) = x
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ sbSet f g ⊢ g (invFun g x) = x TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_right_inv
[25, 1]
[35, 23]
have : ∃ y, g y = x := by simp at this assumption
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ sbSet f g this : x ∈ g '' univ ⊢ g (invFun g x) = x
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ sbSet f g this✝ : x ∈ g '' univ this : ∃ y, g y = x ⊢ g (invFun g x) = x
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ sbSet f g this : x ∈ g '' univ ⊢ g (invFun g x) = x TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_right_inv
[25, 1]
[35, 23]
exact invFun_eq this
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ sbSet f g this✝ : x ∈ g '' univ this : ∃ y, g y = x ⊢ g (invFun g x) = x
no goals
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ sbSet f g this✝ : x ∈ g '' univ this : ∃ y, g y = x ⊢ g (invFun g x) = x TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_right_inv
[25, 1]
[35, 23]
contrapose! hx
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ sbSet f g ⊢ x ∈ g '' univ
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ g '' univ ⊢ x ∈ sbSet f g
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ sbSet f g ⊢ x ∈ g '' univ TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_right_inv
[25, 1]
[35, 23]
rw [sbSet, mem_iUnion]
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ g '' univ ⊢ x ∈ sbSet f g
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ g '' univ ⊢ ∃ i, x ∈ sbAux f g i
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ g '' univ ⊢ x ∈ sbSet f g TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_right_inv
[25, 1]
[35, 23]
use 0
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ g '' univ ⊢ ∃ i, x ∈ sbAux f g i
case h α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ g '' univ ⊢ x ∈ sbAux f g 0
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ g '' univ ⊢ ∃ i, x ∈ sbAux f g i TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_right_inv
[25, 1]
[35, 23]
rw [sbAux, mem_diff]
case h α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ g '' univ ⊢ x ∈ sbAux f g 0
case h α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ g '' univ ⊢ x ∈ univ ∧ x ∉ g '' univ
Please generate a tactic in lean4 to solve the state. STATE: case h α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ g '' univ ⊢ x ∈ sbAux f g 0 TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_right_inv
[25, 1]
[35, 23]
exact ⟨mem_univ _, hx⟩
case h α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ g '' univ ⊢ x ∈ univ ∧ x ∉ g '' univ
no goals
Please generate a tactic in lean4 to solve the state. STATE: case h α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ g '' univ ⊢ x ∈ univ ∧ x ∉ g '' univ TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_right_inv
[25, 1]
[35, 23]
simp at this
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ sbSet f g this : x ∈ g '' univ ⊢ ∃ y, g y = x
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ sbSet f g this : ∃ y, g y = x ⊢ ∃ y, g y = x
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ sbSet f g this : x ∈ g '' univ ⊢ ∃ y, g y = x TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_right_inv
[25, 1]
[35, 23]
assumption
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ sbSet f g this : ∃ y, g y = x ⊢ ∃ y, g y = x
no goals
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α x : α hx : x ∉ sbSet f g this : ∃ y, g y = x ⊢ ∃ y, g y = x TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
set A := sbSet f g with A_def
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f ⊢ Injective (sbFun f g)
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g ⊢ Injective (sbFun f g)
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f ⊢ Injective (sbFun f g) TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
set h := sbFun f g with h_def
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g ⊢ Injective (sbFun f g)
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g ⊢ Injective h
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g ⊢ Injective (sbFun f g) TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
intro x₁ x₂
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g ⊢ Injective h
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α ⊢ h x₁ = h x₂ → x₁ = x₂
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g ⊢ Injective h TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
intro (hxeq : h x₁ = h x₂)
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α ⊢ h x₁ = h x₂ → x₁ = x₂
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : h x₁ = h x₂ ⊢ x₁ = x₂
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α ⊢ h x₁ = h x₂ → x₁ = x₂ TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
simp only [h_def, sbFun, ← A_def] at hxeq
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : h x₁ = h x₂ ⊢ x₁ = x₂
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ ⊢ x₁ = x₂
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : h x₁ = h x₂ ⊢ x₁ = x₂ TACTIC:
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
by_cases xA : x₁ ∈ A ∨ x₂ ∈ A
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ ⊢ x₁ = x₂
case pos α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A ⊢ x₁ = x₂ case neg α :...
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invF...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
push_neg at xA
case neg α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : ¬(x₁ ∈ A ∨ x₂ ∈ A) ⊢ x₁ = x₂
case neg α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : x₁ ∉ A ∧ x₂ ∉ A ⊢ x₁ = x₂
Please generate a tactic in lean4 to solve the state. STATE: case neg α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ ...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
rw [if_neg xA.1, if_neg xA.2] at hxeq
case neg α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : x₁ ∉ A ∧ x₂ ∉ A ⊢ x₁ = x₂
case neg α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : invFun g x₁ = invFun g x₂ xA : x₁ ∉ A ∧ x₂ ∉ A ⊢ x₁ = x₂
Please generate a tactic in lean4 to solve the state. STATE: case neg α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ ...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
rw [← sb_right_inv f g xA.1, hxeq, sb_right_inv f g xA.2]
case neg α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : invFun g x₁ = invFun g x₂ xA : x₁ ∉ A ∧ x₂ ∉ A ⊢ x₁ = x₂
no goals
Please generate a tactic in lean4 to solve the state. STATE: case neg α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : invFun g x₁ = invFun g x₂ xA : x₁ ∉ A ∧ x₂ ∉ A ⊢ x₁ = x₂ TACT...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
wlog x₁A : x₁ ∈ A generalizing x₁ x₂ hxeq xA
case pos α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A ⊢ x₁ = x₂
case pos.inr α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A this : ∀ ⦃x₁ x₂ :...
Please generate a tactic in lean4 to solve the state. STATE: case pos α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ ...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
have x₂A : x₂ ∈ A := by apply not_imp_self.mp intro (x₂nA : x₂ ∉ A) rw [if_pos x₁A, if_neg x₂nA] at hxeq rw [A_def, sbSet, mem_iUnion] at x₁A have x₂eq : x₂ = g (f x₁) := by rw [hxeq, sb_right_inv f g x₂nA] rcases x₁A with ⟨n, hn⟩ rw [A_def, sbSet, mem_iUnion] use n + 1 simp [sbAux] exact ⟨x₁, h...
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : x₁ ∈ A ⊢ x₁ = x₂
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : x₁ ∈ A x₂A : x₂ ∈ A ⊢ x₁ =...
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invF...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
rw [if_pos x₁A, if_pos x₂A] at hxeq
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : x₁ ∈ A x₂A : x₂ ∈ A ⊢ x₁ =...
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : f x₁ = f x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : x₁ ∈ A x₂A : x₂ ∈ A ⊢ x₁ = x₂
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invF...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
exact hf hxeq
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : f x₁ = f x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : x₁ ∈ A x₂A : x₂ ∈ A ⊢ x₁ = x₂
no goals
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : f x₁ = f x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : x₁ ∈ A x₂A : x₂ ∈ A ⊢ x₁ = x₂ T...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
symm
case pos.inr α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A this : ∀ ⦃x₁ x₂ :...
case pos.inr α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A this : ∀ ⦃x₁ x₂ :...
Please generate a tactic in lean4 to solve the state. STATE: case pos.inr α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
apply this hxeq.symm xA.symm (xA.resolve_left x₁A)
case pos.inr α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A this : ∀ ⦃x₁ x₂ :...
no goals
Please generate a tactic in lean4 to solve the state. STATE: case pos.inr α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
apply not_imp_self.mp
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : x₁ ∈ A ⊢ x₂ ∈ A
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : x₁ ∈ A ⊢ x₂ ∉ A → x₂ ∈ A
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invF...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
intro (x₂nA : x₂ ∉ A)
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : x₁ ∈ A ⊢ x₂ ∉ A → x₂ ∈ A
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : x₁ ∈ A x₂nA : x₂ ∉ A ⊢ x₂ ...
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invF...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
rw [if_pos x₁A, if_neg x₂nA] at hxeq
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : x₁ ∈ A x₂nA : x₂ ∉ A ⊢ x₂ ...
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : f x₁ = invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : x₁ ∈ A x₂nA : x₂ ∉ A ⊢ x₂ ∈ A
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : (if x₁ ∈ A then f x₁ else invFun g x₁) = if x₂ ∈ A then f x₂ else invF...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
rw [A_def, sbSet, mem_iUnion] at x₁A
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : f x₁ = invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : x₁ ∈ A x₂nA : x₂ ∉ A ⊢ x₂ ∈ A
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : f x₁ = invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : ∃ i, x₁ ∈ sbAux f g i x₂nA : x₂ ∉ A ⊢ x₂ ∈ A
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : f x₁ = invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : x₁ ∈ A x₂nA : x₂ ∉ A ⊢ x...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
have x₂eq : x₂ = g (f x₁) := by rw [hxeq, sb_right_inv f g x₂nA]
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : f x₁ = invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : ∃ i, x₁ ∈ sbAux f g i x₂nA : x₂ ∉ A ⊢ x₂ ∈ A
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : f x₁ = invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : ∃ i, x₁ ∈ sbAux f g i x₂nA : x₂ ∉ A x₂eq : x₂ = g (f x₁) ⊢ x₂ ∈ A
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : f x₁ = invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : ∃ i, x₁ ∈ sbAux f g i x₂...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
rcases x₁A with ⟨n, hn⟩
α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : f x₁ = invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : ∃ i, x₁ ∈ sbAux f g i x₂nA : x₂ ∉ A x₂eq : x₂ = g (f x₁) ⊢ x₂ ∈ A
case intro α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : f x₁ = invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₂nA : x₂ ∉ A x₂eq : x₂ = g (f x₁) n : ℕ hn : x₁ ∈ sbAux f g n ⊢ x₂ ∈ A
Please generate a tactic in lean4 to solve the state. STATE: α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : f x₁ = invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₁A : ∃ i, x₁ ∈ sbAux f g i x₂...
https://github.com/fpvandoorn/LeanInRome.git
55e064179515cdc8f96fd8e82b2c106fb80e5c0e
LeanInRome/S4_Sets_and_Functions/solutions/Solutions_S03_The_Schroeder_Bernstein_Theorem.lean
sb_injective
[37, 1]
[64, 60]
rw [A_def, sbSet, mem_iUnion]
case intro α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : f x₁ = invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₂nA : x₂ ∉ A x₂eq : x₂ = g (f x₁) n : ℕ hn : x₁ ∈ sbAux f g n ⊢ x₂ ∈ A
case intro α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : f x₁ = invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₂nA : x₂ ∉ A x₂eq : x₂ = g (f x₁) n : ℕ hn : x₁ ∈ sbAux f g n ⊢ ∃ i, x₂ ∈ sbAux...
Please generate a tactic in lean4 to solve the state. STATE: case intro α : Type u_1 β : Type u_2 inst✝ : Nonempty β f : α → β g : β → α hf : Injective f A : Set α := sbSet f g A_def : A = sbSet f g h : α → β := sbFun f g h_def : h = sbFun f g x₁ x₂ : α hxeq : f x₁ = invFun g x₂ xA : x₁ ∈ A ∨ x₂ ∈ A x₂nA : x₂ ∉ A x₂eq ...