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import Mathlib.Topology.UniformSpace.CompleteSeparated import Mathlib.Topology.EMetricSpace.Lipschitz import Mathlib.Topology.MetricSpace.Basic import Mathlib.Topology.MetricSpace.Bounded #align_import topology.metric_space.antilipschitz from "leanprover-community/mathlib"@"c8f305514e0d47dfaa710f5a52f0d21b588e6328" ...
Mathlib/Topology/MetricSpace/Antilipschitz.lean
53
56
theorem antilipschitzWith_iff_le_mul_nndist : AntilipschitzWith K f ↔ ∀ x y, nndist x y ≤ K * nndist (f x) (f y) := by
simp only [AntilipschitzWith, edist_nndist] norm_cast
2
import Mathlib.Dynamics.Ergodic.MeasurePreserving import Mathlib.LinearAlgebra.Determinant import Mathlib.LinearAlgebra.Matrix.Diagonal import Mathlib.LinearAlgebra.Matrix.Transvection import Mathlib.MeasureTheory.Group.LIntegral import Mathlib.MeasureTheory.Integral.Marginal import Mathlib.MeasureTheory.Measure.Stiel...
Mathlib/MeasureTheory/Measure/Lebesgue/Basic.lean
100
104
theorem volume_univ : volume (univ : Set ℝ) = ∞ := ENNReal.eq_top_of_forall_nnreal_le fun r => calc (r : ℝ≥0∞) = volume (Icc (0 : ℝ) r) := by
simp _ ≤ volume univ := measure_mono (subset_univ _)
2
import Mathlib.LinearAlgebra.Matrix.ToLin import Mathlib.LinearAlgebra.Quotient import Mathlib.RingTheory.Ideal.Maps import Mathlib.RingTheory.Nilpotent.Defs #align_import ring_theory.nilpotent from "leanprover-community/mathlib"@"da420a8c6dd5bdfb85c4ced85c34388f633bc6ff" universe u v open Function Set variable ...
Mathlib/RingTheory/Nilpotent/Lemmas.lean
32
35
theorem isRadical_iff_span_singleton [CommSemiring R] : IsRadical y ↔ (Ideal.span ({y} : Set R)).IsRadical := by
simp_rw [IsRadical, ← Ideal.mem_span_singleton] exact forall_swap.trans (forall_congr' fun r => exists_imp.symm)
2
import Mathlib.Data.Matrix.Basis import Mathlib.LinearAlgebra.Basis import Mathlib.LinearAlgebra.Pi #align_import linear_algebra.std_basis from "leanprover-community/mathlib"@"13bce9a6b6c44f6b4c91ac1c1d2a816e2533d395" open Function Set Submodule namespace LinearMap variable (R : Type*) {ι : Type*} [Semiring R] ...
Mathlib/LinearAlgebra/StdBasis.lean
55
57
theorem stdBasis_apply' (i i' : ι) : (stdBasis R (fun _x : ι => R) i) 1 i' = ite (i = i') 1 0 := by
rw [LinearMap.stdBasis_apply, Function.update_apply, Pi.zero_apply] congr 1; rw [eq_iff_iff, eq_comm]
2
import Mathlib.NumberTheory.LegendreSymbol.QuadraticChar.Basic #align_import number_theory.legendre_symbol.basic from "leanprover-community/mathlib"@"5b2fe80501ff327b9109fb09b7cc8c325cd0d7d9" open Nat section Euler section Legendre open ZMod variable (p : ℕ) [Fact p.Prime] def legendreSym (a : ℤ) : ℤ := ...
Mathlib/NumberTheory/LegendreSymbol/Basic.lean
294
296
theorem legendreSym.at_neg_one (hp : p ≠ 2) : legendreSym p (-1) = χ₄ p := by
simp only [legendreSym, card p, quadraticChar_neg_one ((ringChar_zmod_n p).substr hp), Int.cast_neg, Int.cast_one]
2
import Mathlib.Algebra.CharP.Invertible import Mathlib.Algebra.Order.Invertible import Mathlib.Algebra.Order.Module.OrderedSMul import Mathlib.Algebra.Order.Group.Instances import Mathlib.LinearAlgebra.AffineSpace.Slope import Mathlib.LinearAlgebra.AffineSpace.Midpoint import Mathlib.Tactic.FieldSimp #align_import li...
Mathlib/LinearAlgebra/AffineSpace/Ordered.lean
77
80
theorem lineMap_strict_mono_endpoints (ha : a < a') (hb : b < b') (h₀ : 0 ≤ r) (h₁ : r ≤ 1) : lineMap a b r < lineMap a' b' r := by
rcases h₀.eq_or_lt with (rfl | h₀); · simpa exact (lineMap_mono_left ha.le h₁).trans_lt (lineMap_strict_mono_right hb h₀)
2
import Mathlib.LinearAlgebra.AffineSpace.AffineMap import Mathlib.Tactic.FieldSimp #align_import linear_algebra.affine_space.slope from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a" open AffineMap variable {k E PE : Type*} [Field k] [AddCommGroup E] [Module k E] [AddTorsor E PE] def ...
Mathlib/LinearAlgebra/AffineSpace/Slope.lean
67
69
theorem slope_vadd_const (f : k → E) (c : PE) : (slope fun x => f x +ᵥ c) = slope f := by
ext a b simp only [slope, vadd_vsub_vadd_cancel_right, vsub_eq_sub]
2
import Mathlib.Data.Finset.Prod import Mathlib.Data.Set.Finite #align_import data.finset.n_ary from "leanprover-community/mathlib"@"eba7871095e834365616b5e43c8c7bb0b37058d0" open Function Set variable {α α' β β' γ γ' δ δ' ε ε' ζ ζ' ν : Type*} namespace Finset variable [DecidableEq α'] [DecidableEq β'] [Decidabl...
Mathlib/Data/Finset/NAry.lean
58
61
theorem card_image₂_iff : (image₂ f s t).card = s.card * t.card ↔ (s ×ˢ t : Set (α × β)).InjOn fun x => f x.1 x.2 := by
rw [← card_product, ← coe_product] exact card_image_iff
2
import Mathlib.Algebra.Homology.ComplexShape import Mathlib.CategoryTheory.Subobject.Limits import Mathlib.CategoryTheory.GradedObject import Mathlib.Algebra.Homology.ShortComplex.Basic #align_import algebra.homology.homological_complex from "leanprover-community/mathlib"@"88bca0ce5d22ebfd9e73e682e51d60ea13b48347" ...
Mathlib/Algebra/Homology/HomologicalComplex.lean
286
290
theorem eqToHom_f {C₁ C₂ : HomologicalComplex V c} (h : C₁ = C₂) (n : ι) : HomologicalComplex.Hom.f (eqToHom h) n = eqToHom (congr_fun (congr_arg HomologicalComplex.X h) n) := by
subst h rfl
2
import Mathlib.CategoryTheory.Subobject.Limits #align_import algebra.homology.image_to_kernel from "leanprover-community/mathlib"@"618ea3d5c99240cd7000d8376924906a148bf9ff" universe v u w open CategoryTheory CategoryTheory.Limits variable {ι : Type*} variable {V : Type u} [Category.{v} V] [HasZeroMorphisms V] o...
Mathlib/Algebra/Homology/ImageToKernel.lean
101
105
theorem imageToKernel_zero_right [HasImages V] {w} : imageToKernel f (0 : B ⟶ C) w = (imageSubobject f).arrow ≫ inv (kernelSubobject (0 : B ⟶ C)).arrow := by
ext simp
2
import Mathlib.Analysis.InnerProductSpace.PiL2 import Mathlib.LinearAlgebra.Matrix.ZPow #align_import linear_algebra.matrix.hermitian from "leanprover-community/mathlib"@"caa58cbf5bfb7f81ccbaca4e8b8ac4bc2b39cc1c" namespace Matrix variable {α β : Type*} {m n : Type*} {A : Matrix n n α} open scoped Matrix local ...
Mathlib/LinearAlgebra/Matrix/Hermitian.lean
74
76
theorem IsHermitian.transpose {A : Matrix n n α} (h : A.IsHermitian) : Aᵀ.IsHermitian := by
rw [IsHermitian, conjTranspose, transpose_map] exact congr_arg Matrix.transpose h
2
import Mathlib.Data.Matrix.Basis import Mathlib.Data.Matrix.DMatrix import Mathlib.LinearAlgebra.Matrix.Determinant.Basic import Mathlib.LinearAlgebra.Matrix.Reindex import Mathlib.Tactic.FieldSimp #align_import linear_algebra.matrix.transvection from "leanprover-community/mathlib"@"0e2aab2b0d521f060f62a14d2cf2e2c54e...
Mathlib/LinearAlgebra/Matrix/Transvection.lean
205
207
theorem inv_mul (t : TransvectionStruct n R) : t.inv.toMatrix * t.toMatrix = 1 := by
rcases t with ⟨_, _, t_hij⟩ simp [toMatrix, transvection_mul_transvection_same, t_hij]
2
import Mathlib.Logic.Relation import Mathlib.Data.List.Forall2 import Mathlib.Data.List.Lex import Mathlib.Data.List.Infix #align_import data.list.chain from "leanprover-community/mathlib"@"dd71334db81d0bd444af1ee339a29298bef40734" -- Make sure we haven't imported `Data.Nat.Order.Basic` assert_not_exists OrderedSu...
Mathlib/Data/List/Chain.lean
62
65
theorem chain_split {a b : α} {l₁ l₂ : List α} : Chain R a (l₁ ++ b :: l₂) ↔ Chain R a (l₁ ++ [b]) ∧ Chain R b l₂ := by
induction' l₁ with x l₁ IH generalizing a <;> simp only [*, nil_append, cons_append, Chain.nil, chain_cons, and_true_iff, and_assoc]
2
import Mathlib.Algebra.Module.Equiv import Mathlib.Data.DFinsupp.Basic import Mathlib.Data.Finsupp.Basic #align_import data.finsupp.to_dfinsupp from "leanprover-community/mathlib"@"59694bd07f0a39c5beccba34bd9f413a160782bf" variable {ι : Type*} {R : Type*} {M : Type*} section Defs def Finsupp.toDFinsupp [Zer...
Mathlib/Data/Finsupp/ToDFinsupp.lean
97
99
theorem toDFinsupp_support (f : ι →₀ M) : f.toDFinsupp.support = f.support := by
ext simp
2
import Mathlib.Algebra.Polynomial.AlgebraMap import Mathlib.Algebra.Polynomial.Monic #align_import data.polynomial.lifts from "leanprover-community/mathlib"@"63417e01fbc711beaf25fa73b6edb395c0cfddd0" open Polynomial noncomputable section namespace Polynomial universe u v w section Semiring variable {R : Type...
Mathlib/Algebra/Polynomial/Lifts.lean
274
276
theorem mapAlg_eq_map (p : R[X]) : mapAlg R S p = map (algebraMap R S) p := by
simp only [mapAlg, aeval_def, eval₂_eq_sum, map, algebraMap_apply, RingHom.coe_comp] ext; congr
2
import Mathlib.Order.ConditionallyCompleteLattice.Basic import Mathlib.Order.RelIso.Basic #align_import order.ord_continuous from "leanprover-community/mathlib"@"207cfac9fcd06138865b5d04f7091e46d9320432" universe u v w x variable {α : Type u} {β : Type v} {γ : Type w} {ι : Sort x} open Function OrderDual Set ...
Mathlib/Order/OrdContinuous.lean
135
137
theorem map_iSup (hf : LeftOrdContinuous f) (g : ι → α) : f (⨆ i, g i) = ⨆ i, f (g i) := by
simp only [iSup, hf.map_sSup', ← range_comp] rfl
2
import Aesop import Mathlib.Algebra.Group.Defs import Mathlib.Data.Nat.Defs import Mathlib.Data.Int.Defs import Mathlib.Logic.Function.Basic import Mathlib.Tactic.Cases import Mathlib.Tactic.SimpRw import Mathlib.Tactic.SplitIfs #align_import algebra.group.basic from "leanprover-community/mathlib"@"a07d750983b94c530a...
Mathlib/Algebra/Group/Basic.lean
128
130
theorem comp_mul_right (x y : α) : (· * x) ∘ (· * y) = (· * (y * x)) := by
ext z simp [mul_assoc]
2
import Mathlib.Order.Cover import Mathlib.Order.LatticeIntervals import Mathlib.Order.GaloisConnection #align_import order.modular_lattice from "leanprover-community/mathlib"@"207cfac9fcd06138865b5d04f7091e46d9320432" open Set variable {α : Type*} class IsWeakUpperModularLattice (α : Type*) [Lattice α] : Prop ...
Mathlib/Order/ModularLattice.lean
181
183
theorem inf_covBy_of_covBy_sup_right : b ⋖ a ⊔ b → a ⊓ b ⋖ a := by
rw [inf_comm, sup_comm] exact inf_covBy_of_covBy_sup_left
2
import Mathlib.Analysis.Calculus.Deriv.Basic import Mathlib.Analysis.Calculus.ContDiff.Defs #align_import analysis.calculus.iterated_deriv from "leanprover-community/mathlib"@"3bce8d800a6f2b8f63fe1e588fd76a9ff4adcebe" noncomputable section open scoped Classical Topology open Filter Asymptotics Set variable {𝕜...
Mathlib/Analysis/Calculus/IteratedDeriv/Defs.lean
69
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theorem iteratedDerivWithin_univ : iteratedDerivWithin n f univ = iteratedDeriv n f := by
ext x rw [iteratedDerivWithin, iteratedDeriv, iteratedFDerivWithin_univ]
2
import Mathlib.Algebra.Group.Prod import Mathlib.Order.Cover #align_import algebra.support from "leanprover-community/mathlib"@"29cb56a7b35f72758b05a30490e1f10bd62c35c1" assert_not_exists MonoidWithZero open Set namespace Function variable {α β A B M N P G : Type*} section One variable [One M] [One N] [One P] ...
Mathlib/Algebra/Group/Support.lean
73
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theorem mulSupport_eq_iff {f : α → M} {s : Set α} : mulSupport f = s ↔ (∀ x, x ∈ s → f x ≠ 1) ∧ ∀ x, x ∉ s → f x = 1 := by
simp (config := { contextual := true }) only [ext_iff, mem_mulSupport, ne_eq, iff_def, not_imp_comm, and_comm, forall_and]
2
import Mathlib.Data.ENat.Lattice import Mathlib.Order.OrderIsoNat import Mathlib.Tactic.TFAE #align_import order.height from "leanprover-community/mathlib"@"bf27744463e9620ca4e4ebe951fe83530ae6949b" open List hiding le_antisymm open OrderDual universe u v variable {α β : Type*} namespace Set section LT varia...
Mathlib/Order/Height.lean
70
73
theorem cons_mem_subchain_iff : (a::l) ∈ s.subchain ↔ a ∈ s ∧ l ∈ s.subchain ∧ ∀ b ∈ l.head?, a < b := by
simp only [subchain, mem_setOf_eq, forall_mem_cons, chain'_cons', and_left_comm, and_comm, and_assoc]
2
import Mathlib.Algebra.Polynomial.BigOperators import Mathlib.Algebra.Polynomial.Derivative import Mathlib.Data.Nat.Choose.Cast import Mathlib.Data.Nat.Choose.Vandermonde import Mathlib.Tactic.FieldSimp #align_import data.polynomial.hasse_deriv from "leanprover-community/mathlib"@"a148d797a1094ab554ad4183a4ad6f130358...
Mathlib/Algebra/Polynomial/HasseDeriv.lean
137
139
theorem hasseDeriv_X (hk : 1 < k) : hasseDeriv k (X : R[X]) = 0 := by
rw [← monomial_one_one_eq_X, hasseDeriv_monomial, Nat.choose_eq_zero_of_lt hk, Nat.cast_zero, zero_mul, monomial_zero_right]
2
import Mathlib.CategoryTheory.Balanced import Mathlib.CategoryTheory.LiftingProperties.Basic #align_import category_theory.limits.shapes.strong_epi from "leanprover-community/mathlib"@"32253a1a1071173b33dc7d6a218cf722c6feb514" universe v u namespace CategoryTheory variable {C : Type u} [Category.{v} C] variable...
Mathlib/CategoryTheory/Limits/Shapes/StrongEpi.lean
127
135
theorem strongMono_of_strongMono [StrongMono (f ≫ g)] : StrongMono f := { mono := mono_of_mono f g rlp := fun {X Y} z => by intros constructor intro u v sq have h₀ : u ≫ f ≫ g = z ≫ v ≫ g := by
rw [← Category.assoc, eq_whisker sq.w, Category.assoc] exact CommSq.HasLift.mk' ⟨(CommSq.mk h₀).lift, by simp, by simp [← cancel_epi z, sq.w]⟩ }
2
import Mathlib.Algebra.Order.Ring.Int import Mathlib.Data.Nat.SuccPred #align_import data.int.succ_pred from "leanprover-community/mathlib"@"9003f28797c0664a49e4179487267c494477d853" open Function Order namespace Int -- so that Lean reads `Int.succ` through `SuccOrder.succ` @[instance] abbrev instSuccOrder : Su...
Mathlib/Data/Int/SuccPred.lean
88
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theorem natCast_covBy {a b : ℕ} : (a : ℤ) ⋖ b ↔ a ⋖ b := by
rw [Nat.covBy_iff_succ_eq, Int.covBy_iff_succ_eq] exact Int.natCast_inj
2
import Mathlib.Data.Int.Range import Mathlib.Data.ZMod.Basic import Mathlib.NumberTheory.MulChar.Basic #align_import number_theory.legendre_symbol.zmod_char from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a" namespace ZMod section QuadCharModP @[simps] def χ₄ : MulChar (ZMod 4) ℤ...
Mathlib/NumberTheory/LegendreSymbol/ZModChar.lean
101
103
theorem χ₄_nat_three_mod_four {n : ℕ} (hn : n % 4 = 3) : χ₄ n = -1 := by
rw [χ₄_nat_mod_four, hn] rfl
2
import Mathlib.LinearAlgebra.Basis import Mathlib.LinearAlgebra.Dual import Mathlib.Data.Fin.FlagRange open Set Submodule namespace Basis section Semiring variable {R M : Type*} [Semiring R] [AddCommMonoid M] [Module R M] {n : ℕ} def flag (b : Basis (Fin n) R M) (k : Fin (n + 1)) : Submodule R M := .span R <...
Mathlib/LinearAlgebra/Basis/Flag.lean
42
45
theorem flag_succ (b : Basis (Fin n) R M) (k : Fin n) : b.flag k.succ = (R ∙ b k) ⊔ b.flag k.castSucc := by
simp only [flag, Fin.castSucc_lt_castSucc_iff] simp [Fin.castSucc_lt_iff_succ_le, le_iff_eq_or_lt, setOf_or, image_insert_eq, span_insert]
2
import Mathlib.CategoryTheory.Functor.Hom import Mathlib.CategoryTheory.Products.Basic import Mathlib.Data.ULift #align_import category_theory.yoneda from "leanprover-community/mathlib"@"369525b73f229ccd76a6ec0e0e0bf2be57599768" namespace CategoryTheory open Opposite universe v₁ u₁ u₂ -- morphism levels before ...
Mathlib/CategoryTheory/Yoneda.lean
255
258
theorem coreprW_app_hom (X : C) (f : F.coreprX ⟶ X) : (F.coreprW.app X).hom f = F.map f F.coreprx := by
simp only [coyoneda_obj_obj, unop_op, Iso.app_hom, coreprx, ← FunctorToTypes.naturality, coyoneda_obj_map, Category.id_comp]
2
import Mathlib.Algebra.GCDMonoid.Basic import Mathlib.Data.Multiset.FinsetOps import Mathlib.Data.Multiset.Fold #align_import algebra.gcd_monoid.multiset from "leanprover-community/mathlib"@"f694c7dead66f5d4c80f446c796a5aad14707f0e" namespace Multiset variable {α : Type*} [CancelCommMonoidWithZero α] [NormalizedG...
Mathlib/Algebra/GCDMonoid/Multiset.lean
207
209
theorem gcd_ndunion (s₁ s₂ : Multiset α) : (ndunion s₁ s₂).gcd = GCDMonoid.gcd s₁.gcd s₂.gcd := by
rw [← gcd_dedup, dedup_ext.2, gcd_dedup, gcd_add] simp
2
import Mathlib.Data.SetLike.Basic import Mathlib.Data.Finset.Preimage import Mathlib.ModelTheory.Semantics #align_import model_theory.definability from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a" universe u v w u₁ namespace Set variable {M : Type w} (A : Set M) (L : FirstOrder.Lang...
Mathlib/ModelTheory/Definability.lean
141
144
theorem definable_finset_biInter {ι : Type*} {f : ι → Set (α → M)} (hf : ∀ i, A.Definable L (f i)) (s : Finset ι) : A.Definable L (⋂ i ∈ s, f i) := by
rw [← Finset.inf_set_eq_iInter] exact definable_finset_inf hf s
2
import Mathlib.Order.Filter.Basic #align_import order.filter.prod from "leanprover-community/mathlib"@"d6fad0e5bf2d6f48da9175d25c3dc5706b3834ce" open Set open Filter namespace Filter variable {α β γ δ : Type*} {ι : Sort*} section Prod variable {s : Set α} {t : Set β} {f : Filter α} {g : Filter β} protected ...
Mathlib/Order/Filter/Prod.lean
117
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theorem top_prod : (⊤ : Filter α) ×ˢ g = g.comap Prod.snd := by
dsimp only [SProd.sprod] rw [Filter.prod, comap_top, top_inf_eq]
2
import Mathlib.Algebra.ModEq import Mathlib.Algebra.Module.Defs import Mathlib.Algebra.Order.Archimedean import Mathlib.Algebra.Periodic import Mathlib.Data.Int.SuccPred import Mathlib.GroupTheory.QuotientGroup import Mathlib.Order.Circular import Mathlib.Data.List.TFAE import Mathlib.Data.Set.Lattice #align_import a...
Mathlib/Algebra/Order/ToIntervalMod.lean
87
89
theorem toIcoMod_mem_Ico' (b : α) : toIcoMod hp 0 b ∈ Set.Ico 0 p := by
convert toIcoMod_mem_Ico hp 0 b exact (zero_add p).symm
2
import Mathlib.Data.Matrix.Invertible import Mathlib.LinearAlgebra.Matrix.NonsingularInverse import Mathlib.LinearAlgebra.Matrix.PosDef #align_import linear_algebra.matrix.schur_complement from "leanprover-community/mathlib"@"a176cb1219e300e85793d44583dede42377b51af" variable {l m n α : Type*} namespace Matrix ...
Mathlib/LinearAlgebra/Matrix/SchurComplement.lean
100
104
theorem invOf_fromBlocks_zero₂₁_eq (A : Matrix m m α) (B : Matrix m n α) (D : Matrix n n α) [Invertible A] [Invertible D] [Invertible (fromBlocks A B 0 D)] : ⅟ (fromBlocks A B 0 D) = fromBlocks (⅟ A) (-(⅟ A * B * ⅟ D)) 0 (⅟ D) := by
letI := fromBlocksZero₂₁Invertible A B D convert (rfl : ⅟ (fromBlocks A B 0 D) = _)
2
import Mathlib.Topology.Instances.Irrational import Mathlib.Topology.Instances.Rat import Mathlib.Topology.Compactification.OnePoint #align_import topology.instances.rat_lemmas from "leanprover-community/mathlib"@"92ca63f0fb391a9ca5f22d2409a6080e786d99f7" open Set Metric Filter TopologicalSpace open Topology One...
Mathlib/Topology/Instances/RatLemmas.lean
72
74
theorem not_firstCountableTopology_opc : ¬FirstCountableTopology ℚ∞ := by
intro exact not_countably_generated_nhds_infty_opc inferInstance
2
import Mathlib.Data.SetLike.Basic import Mathlib.Data.Finset.Preimage import Mathlib.ModelTheory.Semantics #align_import model_theory.definability from "leanprover-community/mathlib"@"70fd9563a21e7b963887c9360bd29b2393e6225a" universe u v w u₁ namespace Set variable {M : Type w} (A : Set M) (L : FirstOrder.Lang...
Mathlib/ModelTheory/Definability.lean
147
150
theorem definable_finset_biUnion {ι : Type*} {f : ι → Set (α → M)} (hf : ∀ i, A.Definable L (f i)) (s : Finset ι) : A.Definable L (⋃ i ∈ s, f i) := by
rw [← Finset.sup_set_eq_biUnion] exact definable_finset_sup hf s
2
import Mathlib.Algebra.BigOperators.Group.Finset import Mathlib.Algebra.GroupPower.IterateHom import Mathlib.Algebra.Regular.Basic #align_import algebra.regular.pow from "leanprover-community/mathlib"@"46a64b5b4268c594af770c44d9e502afc6a515cb" variable {R : Type*} {a b : R} section Monoid variable [Monoid R] ...
Mathlib/Algebra/Regular/Pow.lean
36
38
theorem IsRightRegular.pow (n : ℕ) (rra : IsRightRegular a) : IsRightRegular (a ^ n) := by
rw [IsRightRegular, ← mul_right_iterate] exact rra.iterate n
2
import Mathlib.Algebra.Homology.Linear import Mathlib.Algebra.Homology.ShortComplex.HomologicalComplex import Mathlib.Tactic.Abel #align_import algebra.homology.homotopy from "leanprover-community/mathlib"@"618ea3d5c99240cd7000d8376924906a148bf9ff" universe v u open scoped Classical noncomputable section open ...
Mathlib/Algebra/Homology/Homotopy.lean
51
54
theorem dNext_eq (f : ∀ i j, C.X i ⟶ D.X j) {i i' : ι} (w : c.Rel i i') : dNext i f = C.d i i' ≫ f i' i := by
obtain rfl := c.next_eq' w rfl
2
import Mathlib.Algebra.Algebra.Tower import Mathlib.Algebra.GroupWithZero.NonZeroDivisors import Mathlib.GroupTheory.MonoidLocalization import Mathlib.RingTheory.Ideal.Basic import Mathlib.GroupTheory.GroupAction.Ring #align_import ring_theory.localization.basic from "leanprover-community/mathlib"@"b69c9a770ecf37eb21...
Mathlib/RingTheory/Localization/Basic.lean
222
225
theorem eq_zero_of_fst_eq_zero {z x} {y : M} (h : z * algebraMap R S y = algebraMap R S x) (hx : x = 0) : z = 0 := by
rw [hx, (algebraMap R S).map_zero] at h exact (IsUnit.mul_left_eq_zero (IsLocalization.map_units S y)).1 h
2
import Mathlib.Algebra.Group.Hom.End import Mathlib.Algebra.Ring.Invertible import Mathlib.Algebra.SMulWithZero import Mathlib.Data.Int.Cast.Lemmas import Mathlib.GroupTheory.GroupAction.Units #align_import algebra.module.basic from "leanprover-community/mathlib"@"30413fc89f202a090a54d78e540963ed3de0056e" assert_n...
Mathlib/Algebra/Module/Defs.lean
241
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theorem Module.ext' {R : Type*} [Semiring R] {M : Type*} [AddCommMonoid M] (P Q : Module R M) (w : ∀ (r : R) (m : M), (haveI := P; r • m) = (haveI := Q; r • m)) : P = Q := by
ext exact w _ _
2
import Mathlib.Order.Filter.Cofinite #align_import topology.bornology.basic from "leanprover-community/mathlib"@"8631e2d5ea77f6c13054d9151d82b83069680cb1" open Set Filter variable {ι α β : Type*} class Bornology (α : Type*) where cobounded' : Filter α le_cofinite' : cobounded' ≤ cofinite #align borno...
Mathlib/Topology/Bornology/Basic.lean
161
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theorem isBounded_empty : IsBounded (∅ : Set α) := by
rw [isBounded_def, compl_empty] exact univ_mem
2
import Mathlib.Algebra.GroupWithZero.Hom import Mathlib.Algebra.Order.Group.Instances import Mathlib.Algebra.Order.GroupWithZero.Canonical import Mathlib.Order.Hom.Basic #align_import algebra.order.hom.monoid from "leanprover-community/mathlib"@"3342d1b2178381196f818146ff79bc0e7ccd9e2d" open Function variable {F...
Mathlib/Algebra/Order/Hom/Monoid.lean
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theorem map_nonpos (ha : a ≤ 0) : f a ≤ 0 := by
rw [← map_zero f] exact OrderHomClass.mono _ ha
2
import Mathlib.Topology.MetricSpace.Antilipschitz #align_import topology.metric_space.isometry from "leanprover-community/mathlib"@"b1859b6d4636fdbb78c5d5cefd24530653cfd3eb" noncomputable section universe u v w variable {ι : Type*} {α : Type u} {β : Type v} {γ : Type w} open Function Set open scoped Topology ...
Mathlib/Topology/MetricSpace/Isometry.lean
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theorem preimage_emetric_ball (h : Isometry f) (x : α) (r : ℝ≥0∞) : f ⁻¹' EMetric.ball (f x) r = EMetric.ball x r := by
ext y simp [h.edist_eq]
2
import Mathlib.CategoryTheory.Functor.ReflectsIso import Mathlib.CategoryTheory.MorphismProperty.Basic universe w v v' u u' namespace CategoryTheory namespace MorphismProperty variable {C : Type u} [Category.{v} C] {D : Type u'} [Category.{v'} D] def IsInvertedBy (P : MorphismProperty C) (F : C ⥤ D) : Prop := ...
Mathlib/CategoryTheory/MorphismProperty/IsInvertedBy.lean
128
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theorem IsInvertedBy.iff_of_iso (W : MorphismProperty C) {F₁ F₂ : C ⥤ D} (e : F₁ ≅ F₂) : W.IsInvertedBy F₁ ↔ W.IsInvertedBy F₂ := by
dsimp [IsInvertedBy] simp only [NatIso.isIso_map_iff e]
2
import Mathlib.Topology.UniformSpace.UniformConvergence import Mathlib.Topology.UniformSpace.UniformEmbedding import Mathlib.Topology.UniformSpace.CompleteSeparated import Mathlib.Topology.UniformSpace.Compact import Mathlib.Topology.Algebra.Group.Basic import Mathlib.Topology.DiscreteSubset import Mathlib.Tactic.Abel...
Mathlib/Topology/Algebra/UniformGroup.lean
103
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theorem UniformContinuous.mul [UniformSpace β] {f : β → α} {g : β → α} (hf : UniformContinuous f) (hg : UniformContinuous g) : UniformContinuous fun x => f x * g x := by
have : UniformContinuous fun x => f x / (g x)⁻¹ := hf.div hg.inv simp_all
2
import Mathlib.RingTheory.IntegralClosure import Mathlib.RingTheory.Localization.Integral #align_import ring_theory.integrally_closed from "leanprover-community/mathlib"@"d35b4ff446f1421bd551fafa4b8efd98ac3ac408" open scoped nonZeroDivisors Polynomial open Polynomial abbrev IsIntegrallyClosedIn (R A : Type*) [...
Mathlib/RingTheory/IntegrallyClosed.lean
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theorem isIntegrallyClosed_iff : IsIntegrallyClosed R ↔ ∀ {x : K}, IsIntegral R x → ∃ y, algebraMap R K y = x := by
simp [isIntegrallyClosed_iff_isIntegrallyClosedIn K, isIntegrallyClosedIn_iff, IsFractionRing.injective R K]
2
import Mathlib.Algebra.Group.Defs #align_import algebra.invertible from "leanprover-community/mathlib"@"722b3b152ddd5e0cf21c0a29787c76596cb6b422" assert_not_exists MonoidWithZero assert_not_exists DenselyOrdered universe u variable {α : Type u} class Invertible [Mul α] [One α] (a : α) : Type u where invOf...
Mathlib/Algebra/Group/Invertible/Defs.lean
156
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theorem invertible_unique {α : Type u} [Monoid α] (a b : α) [Invertible a] [Invertible b] (h : a = b) : ⅟ a = ⅟ b := by
apply invOf_eq_right_inv rw [h, mul_invOf_self]
2
import Mathlib.Analysis.InnerProductSpace.Dual import Mathlib.Analysis.InnerProductSpace.PiL2 #align_import analysis.inner_product_space.adjoint from "leanprover-community/mathlib"@"46b633fd842bef9469441c0209906f6dddd2b4f5" noncomputable section open RCLike open scoped ComplexConjugate variable {𝕜 E F G : Type...
Mathlib/Analysis/InnerProductSpace/Adjoint.lean
80
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theorem adjointAux_inner_left (A : E →L[𝕜] F) (x : E) (y : F) : ⟪adjointAux A y, x⟫ = ⟪y, A x⟫ := by
rw [adjointAux_apply, toDual_symm_apply, toSesqForm_apply_coe, coe_comp', innerSL_apply_coe, Function.comp_apply]
2
import Mathlib.AlgebraicTopology.SimplexCategory import Mathlib.CategoryTheory.Comma.Arrow import Mathlib.CategoryTheory.Limits.FunctorCategory import Mathlib.CategoryTheory.Opposites #align_import algebraic_topology.simplicial_object from "leanprover-community/mathlib"@"5ed51dc37c6b891b79314ee11a50adc2b1df6fd6" o...
Mathlib/AlgebraicTopology/SimplicialObject.lean
138
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theorem δ_comp_δ_self' {n} {j : Fin (n + 3)} {i : Fin (n + 2)} (H : j = Fin.castSucc i) : X.δ j ≫ X.δ i = X.δ i.succ ≫ X.δ i := by
subst H rw [δ_comp_δ_self]
2
import Mathlib.Algebra.Polynomial.AlgebraMap import Mathlib.Algebra.Polynomial.BigOperators import Mathlib.Algebra.Polynomial.Degree.Lemmas import Mathlib.Algebra.Polynomial.Div #align_import data.polynomial.ring_division from "leanprover-community/mathlib"@"8efcf8022aac8e01df8d302dcebdbc25d6a886c8" noncomputable ...
Mathlib/Algebra/Polynomial/RingDivision.lean
156
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theorem natDegree_le_of_dvd {p q : R[X]} (h1 : p ∣ q) (h2 : q ≠ 0) : p.natDegree ≤ q.natDegree := by
rcases h1 with ⟨q, rfl⟩; rw [mul_ne_zero_iff] at h2 rw [natDegree_mul h2.1 h2.2]; exact Nat.le_add_right _ _
2
import Mathlib.Algebra.Field.Defs import Mathlib.Algebra.GroupWithZero.Units.Lemmas import Mathlib.Algebra.Ring.Commute import Mathlib.Algebra.Ring.Invertible import Mathlib.Order.Synonym #align_import algebra.field.basic from "leanprover-community/mathlib"@"05101c3df9d9cfe9430edc205860c79b6d660102" open Function ...
Mathlib/Algebra/Field/Basic.lean
96
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theorem one_div_neg_one_eq_neg_one : (1 : K) / -1 = -1 := have : -1 * -1 = (1 : K) := by
rw [neg_mul_neg, one_mul] Eq.symm (eq_one_div_of_mul_eq_one_right this)
2
import Mathlib.Analysis.SpecialFunctions.Exp import Mathlib.Tactic.Positivity.Core import Mathlib.Algebra.Ring.NegOnePow #align_import analysis.special_functions.trigonometric.basic from "leanprover-community/mathlib"@"2c1d8ca2812b64f88992a5294ea3dba144755cd1" noncomputable section open scoped Classical open Top...
Mathlib/Analysis/SpecialFunctions/Trigonometric/Basic.lean
54
56
theorem continuous_sin : Continuous sin := by
change Continuous fun z => (exp (-z * I) - exp (z * I)) * I / 2 continuity
2
import Mathlib.Analysis.Normed.Group.Basic #align_import information_theory.hamming from "leanprover-community/mathlib"@"17ef379e997badd73e5eabb4d38f11919ab3c4b3" section HammingDistNorm open Finset Function variable {α ι : Type*} {β : ι → Type*} [Fintype ι] [∀ i, DecidableEq (β i)] variable {γ : ι → Type*} [∀ ...
Mathlib/InformationTheory/Hamming.lean
85
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theorem swap_hammingDist : swap (@hammingDist _ β _ _) = hammingDist := by
funext x y exact hammingDist_comm _ _
2
import Mathlib.Algebra.Group.Commute.Units import Mathlib.Algebra.Group.Int import Mathlib.Algebra.GroupWithZero.Semiconj import Mathlib.Data.Nat.GCD.Basic import Mathlib.Order.Bounds.Basic #align_import data.int.gcd from "leanprover-community/mathlib"@"47a1a73351de8dd6c8d3d32b569c8e434b03ca47" namespace Nat ...
Mathlib/Data/Int/GCD.lean
139
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theorem gcd_eq_gcd_ab : (gcd x y : ℤ) = x * gcdA x y + y * gcdB x y := by
have := @xgcdAux_P x y x y 1 0 0 1 (by simp [P]) (by simp [P]) rwa [xgcdAux_val, xgcd_val] at this
2
import Mathlib.MeasureTheory.Measure.FiniteMeasure import Mathlib.MeasureTheory.Integral.Average #align_import measure_theory.measure.probability_measure from "leanprover-community/mathlib"@"f0c8bf9245297a541f468be517f1bde6195105e9" noncomputable section open MeasureTheory open Set open Filter open BoundedCon...
Mathlib/MeasureTheory/Measure/ProbabilityMeasure.lean
193
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theorem ennreal_coeFn_eq_coeFn_toMeasure (ν : ProbabilityMeasure Ω) (s : Set Ω) : (ν s : ℝ≥0∞) = (ν : Measure Ω) s := by
rw [← coeFn_comp_toFiniteMeasure_eq_coeFn, FiniteMeasure.ennreal_coeFn_eq_coeFn_toMeasure, toMeasure_comp_toFiniteMeasure_eq_toMeasure]
2
import Mathlib.Data.Rat.Sqrt import Mathlib.Data.Real.Sqrt import Mathlib.RingTheory.Algebraic import Mathlib.RingTheory.Int.Basic import Mathlib.Tactic.IntervalCases #align_import data.real.irrational from "leanprover-community/mathlib"@"7e7aaccf9b0182576cabdde36cf1b5ad3585b70d" open Rat Real multiplicity def ...
Mathlib/Data/Real/Irrational.lean
32
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theorem irrational_iff_ne_rational (x : ℝ) : Irrational x ↔ ∀ a b : ℤ, x ≠ a / b := by
simp only [Irrational, Rat.forall, cast_mk, not_exists, Set.mem_range, cast_intCast, cast_div, eq_comm]
2
import Mathlib.Algebra.Quotient import Mathlib.Algebra.Group.Subgroup.Actions import Mathlib.Algebra.Group.Subgroup.MulOpposite import Mathlib.GroupTheory.GroupAction.Basic import Mathlib.SetTheory.Cardinal.Finite #align_import group_theory.coset from "leanprover-community/mathlib"@"f7fc89d5d5ff1db2d1242c7bb0e9062ce4...
Mathlib/GroupTheory/Coset.lean
302
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theorem leftRel_apply {x y : α} : @Setoid.r _ (leftRel s) x y ↔ x⁻¹ * y ∈ s := calc (∃ a : s.op, y * MulOpposite.unop a = x) ↔ ∃ a : s, y * a = x := s.equivOp.symm.exists_congr_left _ ↔ ∃ a : s, x⁻¹ * y = a⁻¹ := by
simp only [inv_mul_eq_iff_eq_mul, Subgroup.coe_inv, eq_mul_inv_iff_mul_eq] _ ↔ x⁻¹ * y ∈ s := by simp [exists_inv_mem_iff_exists_mem]
2
import Mathlib.Control.Bifunctor import Mathlib.Logic.Equiv.Defs #align_import logic.equiv.functor from "leanprover-community/mathlib"@"9407b03373c8cd201df99d6bc5514fc2db44054f" universe u v w variable {α β : Type u} open Equiv namespace Bifunctor variable {α' β' : Type v} (F : Type u → Type v → Type w) [Bifu...
Mathlib/Logic/Equiv/Functor.lean
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theorem mapEquiv_refl_refl : mapEquiv F (Equiv.refl α) (Equiv.refl α') = Equiv.refl (F α α') := by
ext x simp [id_bimap]
2
import Mathlib.Algebra.BigOperators.Finsupp import Mathlib.Algebra.BigOperators.Finprod import Mathlib.Data.Fintype.BigOperators import Mathlib.LinearAlgebra.Finsupp import Mathlib.LinearAlgebra.LinearIndependent import Mathlib.SetTheory.Cardinal.Cofinality #align_import linear_algebra.basis from "leanprover-communit...
Mathlib/LinearAlgebra/Basis.lean
137
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theorem repr_symm_single : b.repr.symm (Finsupp.single i c) = c • b i := calc b.repr.symm (Finsupp.single i c) = b.repr.symm (c • Finsupp.single i (1 : R)) := by
{ rw [Finsupp.smul_single', mul_one] } _ = c • b i := by rw [LinearEquiv.map_smul, repr_symm_single_one]
2
import Mathlib.Algebra.BigOperators.Group.List import Mathlib.Algebra.Group.Prod import Mathlib.Data.Multiset.Basic #align_import algebra.big_operators.multiset.basic from "leanprover-community/mathlib"@"6c5f73fd6f6cc83122788a80a27cdd54663609f4" assert_not_exists MonoidWithZero variable {F ι α β γ : Type*} names...
Mathlib/Algebra/BigOperators/Group/Multiset.lean
66
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theorem prod_toList (s : Multiset α) : s.toList.prod = s.prod := by
conv_rhs => rw [← coe_toList s] rw [prod_coe]
2
import Mathlib.Analysis.Normed.Group.Basic #align_import information_theory.hamming from "leanprover-community/mathlib"@"17ef379e997badd73e5eabb4d38f11919ab3c4b3" section HammingDistNorm open Finset Function variable {α ι : Type*} {β : ι → Type*} [Fintype ι] [∀ i, DecidableEq (β i)] variable {γ : ι → Type*} [∀ ...
Mathlib/InformationTheory/Hamming.lean
71
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theorem hammingDist_triangle_left (x y z : ∀ i, β i) : hammingDist x y ≤ hammingDist z x + hammingDist z y := by
rw [hammingDist_comm z] exact hammingDist_triangle _ _ _
2
import Mathlib.Algebra.Group.Commute.Basic import Mathlib.GroupTheory.GroupAction.Basic import Mathlib.Dynamics.PeriodicPts import Mathlib.Data.Set.Pointwise.SMul namespace MulAction open Pointwise variable {α : Type*} variable {G : Type*} [Group G] [MulAction G α] variable {M : Type*} [Monoid M] [MulAction M α] ...
Mathlib/GroupTheory/GroupAction/FixedPoints.lean
65
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theorem smul_mem_fixedBy_iff_mem_fixedBy {a : α} {g : G} : g • a ∈ fixedBy α g ↔ a ∈ fixedBy α g := by
rw [mem_fixedBy, smul_left_cancel_iff] rfl
2
import Mathlib.Analysis.SpecialFunctions.Exp import Mathlib.Data.Nat.Factorization.Basic import Mathlib.Analysis.NormedSpace.Real #align_import analysis.special_functions.log.basic from "leanprover-community/mathlib"@"f23a09ce6d3f367220dc3cecad6b7eb69eb01690" open Set Filter Function open Topology noncomputable ...
Mathlib/Analysis/SpecialFunctions/Log/Basic.lean
137
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theorem log_inv (x : ℝ) : log x⁻¹ = -log x := by
by_cases hx : x = 0; · simp [hx] rw [← exp_eq_exp, exp_log_eq_abs (inv_ne_zero hx), exp_neg, exp_log_eq_abs hx, abs_inv]
2
import Mathlib.LinearAlgebra.Quotient import Mathlib.RingTheory.Ideal.Operations namespace Submodule open Pointwise variable {R M M' F G : Type*} [CommRing R] [AddCommGroup M] [Module R M] variable {N N₁ N₂ P P₁ P₂ : Submodule R M} def colon (N P : Submodule R M) : Ideal R := annihilator (P.map N.mkQ) #align ...
Mathlib/RingTheory/Ideal/Colon.lean
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theorem mem_colon_singleton {N : Submodule R M} {x : M} {r : R} : r ∈ N.colon (Submodule.span R {x}) ↔ r • x ∈ N := calc r ∈ N.colon (Submodule.span R {x}) ↔ ∀ a : R, r • a • x ∈ N := by
simp [Submodule.mem_colon, Submodule.mem_span_singleton] _ ↔ r • x ∈ N := by simp_rw [fun (a : R) ↦ smul_comm r a x]; exact SetLike.forall_smul_mem_iff
2
import Mathlib.Algebra.IsPrimePow import Mathlib.Data.Nat.Factorization.Basic #align_import data.nat.factorization.prime_pow from "leanprover-community/mathlib"@"6ca1a09bc9aa75824bf97388c9e3b441fc4ccf3f" variable {R : Type*} [CommMonoidWithZero R] (n p : R) (k : ℕ) theorem IsPrimePow.minFac_pow_factorization_eq ...
Mathlib/Data/Nat/Factorization/PrimePow.lean
57
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theorem isPrimePow_iff_card_primeFactors_eq_one {n : ℕ} : IsPrimePow n ↔ n.primeFactors.card = 1 := by
simp_rw [isPrimePow_iff_factorization_eq_single, ← Nat.support_factorization, Finsupp.card_support_eq_one', pos_iff_ne_zero]
2
import Mathlib.Algebra.ContinuedFractions.Computation.Basic import Mathlib.Algebra.ContinuedFractions.Translations #align_import algebra.continued_fractions.computation.translations from "leanprover-community/mathlib"@"a7e36e48519ab281320c4d192da6a7b348ce40ad" namespace GeneralizedContinuedFraction open Generali...
Mathlib/Algebra/ContinuedFractions/Computation/Translations.lean
240
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theorem get?_of_eq_some_of_succ_get?_intFractPair_stream {ifp_succ_n : IntFractPair K} (stream_succ_nth_eq : IntFractPair.stream v (n + 1) = some ifp_succ_n) : (of v).s.get? n = some ⟨1, ifp_succ_n.b⟩ := by
unfold of IntFractPair.seq1 simp [Stream'.Seq.map_tail, Stream'.Seq.get?_tail, Stream'.Seq.map_get?, stream_succ_nth_eq]
2
import Mathlib.Algebra.Polynomial.Div import Mathlib.RingTheory.Polynomial.Basic import Mathlib.RingTheory.Ideal.QuotientOperations #align_import ring_theory.polynomial.quotient from "leanprover-community/mathlib"@"4f840b8d28320b20c87db17b3a6eef3d325fca87" set_option linter.uppercaseLean3 false open Polynomial ...
Mathlib/RingTheory/Polynomial/Quotient.lean
158
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theorem polynomialQuotientEquivQuotientPolynomial_map_mk (I : Ideal R) (f : R[X]) : I.polynomialQuotientEquivQuotientPolynomial (f.map <| Quotient.mk I) = Quotient.mk (map C I : Ideal R[X]) f := by
apply (polynomialQuotientEquivQuotientPolynomial I).symm.injective rw [RingEquiv.symm_apply_apply, polynomialQuotientEquivQuotientPolynomial_symm_mk]
2
import Mathlib.LinearAlgebra.AffineSpace.AffineSubspace #align_import linear_algebra.affine_space.restrict from "leanprover-community/mathlib"@"09258fb7f75d741b7eda9fa18d5c869e2135d9f1" variable {k V₁ P₁ V₂ P₂ : Type*} [Ring k] [AddCommGroup V₁] [AddCommGroup V₂] [Module k V₁] [Module k V₂] [AddTorsor V₁ P₁] [A...
Mathlib/LinearAlgebra/AffineSpace/Restrict.lean
33
36
theorem AffineSubspace.nonempty_map {E : AffineSubspace k P₁} [Ene : Nonempty E] {φ : P₁ →ᵃ[k] P₂} : Nonempty (E.map φ) := by
obtain ⟨x, hx⟩ := id Ene exact ⟨⟨φ x, AffineSubspace.mem_map.mpr ⟨x, hx, rfl⟩⟩⟩
2
import Mathlib.FieldTheory.Separable import Mathlib.RingTheory.IntegralDomain import Mathlib.Algebra.CharP.Reduced import Mathlib.Tactic.ApplyFun #align_import field_theory.finite.basic from "leanprover-community/mathlib"@"12a85fac627bea918960da036049d611b1a3ee43" variable {K : Type*} {R : Type*} local notation ...
Mathlib/FieldTheory/Finite/Basic.lean
76
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theorem exists_root_sum_quadratic [Fintype R] {f g : R[X]} (hf2 : degree f = 2) (hg2 : degree g = 2) (hR : Fintype.card R % 2 = 1) : ∃ a b, f.eval a + g.eval b = 0 := letI := Classical.decEq R suffices ¬Disjoint (univ.image fun x : R => eval x f) (univ.image fun x : R => eval x (-g)) by simp only [disjo...
rw [card_union_of_disjoint hd]; simp [natDegree_eq_of_degree_eq_some hf2, natDegree_eq_of_degree_eq_some hg2, mul_add]
2
import Mathlib.Algebra.Ring.Equiv #align_import algebra.ring.comp_typeclasses from "leanprover-community/mathlib"@"207cfac9fcd06138865b5d04f7091e46d9320432" variable {R₁ : Type*} {R₂ : Type*} {R₃ : Type*} variable [Semiring R₁] [Semiring R₂] [Semiring R₃] -- This at first seems not very useful. However we need ...
Mathlib/Algebra/Ring/CompTypeclasses.lean
106
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theorem comp_apply_eq₂ {x : R₂} : σ (σ' x) = x := by
rw [← RingHom.comp_apply, comp_eq₂] simp
2
import Mathlib.Data.Set.Lattice #align_import data.set.intervals.disjoint from "leanprover-community/mathlib"@"207cfac9fcd06138865b5d04f7091e46d9320432" universe u v w variable {ι : Sort u} {α : Type v} {β : Type w} open Set open OrderDual (toDual) namespace Set section LinearOrder variable [LinearOrder α] ...
Mathlib/Order/Interval/Set/Disjoint.lean
143
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theorem Ico_disjoint_Ico : Disjoint (Ico a₁ a₂) (Ico b₁ b₂) ↔ min a₂ b₂ ≤ max a₁ b₁ := by
simp_rw [Set.disjoint_iff_inter_eq_empty, Ico_inter_Ico, Ico_eq_empty_iff, inf_eq_min, sup_eq_max, not_lt]
2
import Mathlib.Order.Interval.Finset.Nat #align_import data.fin.interval from "leanprover-community/mathlib"@"1d29de43a5ba4662dd33b5cfeecfc2a27a5a8a29" assert_not_exists MonoidWithZero open Finset Fin Function namespace Fin variable (n : ℕ) instance instLocallyFiniteOrder : LocallyFiniteOrder (Fin n) := Orde...
Mathlib/Order/Interval/Finset/Fin.lean
156
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theorem Ici_eq_finset_subtype : Ici a = (Icc (a : ℕ) n).fin n := by
ext simp
2
import Mathlib.Data.Finsupp.Basic import Mathlib.Data.Finsupp.Order #align_import data.finsupp.multiset from "leanprover-community/mathlib"@"59694bd07f0a39c5beccba34bd9f413a160782bf" open Finset variable {α β ι : Type*} namespace Finsupp def toMultiset : (α →₀ ℕ) →+ Multiset α where toFun f := Finsupp.sum f...
Mathlib/Data/Finsupp/Multiset.lean
117
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theorem toMultiset_sup [DecidableEq α] (f g : α →₀ ℕ) : toMultiset (f ⊔ g) = toMultiset f ∪ toMultiset g := by
ext simp_rw [Multiset.count_union, Finsupp.count_toMultiset, Finsupp.sup_apply, sup_eq_max]
2
import Mathlib.CategoryTheory.Limits.Preserves.Shapes.BinaryProducts import Mathlib.CategoryTheory.Limits.Preserves.Shapes.Products import Mathlib.CategoryTheory.Limits.ConcreteCategory import Mathlib.CategoryTheory.Limits.Shapes.Types import Mathlib.CategoryTheory.Limits.Shapes.Multiequalizer import Mathlib.CategoryT...
Mathlib/CategoryTheory/Limits/Shapes/ConcreteCategory.lean
349
353
theorem cokernel_funext {C : Type*} [Category C] [HasZeroMorphisms C] [ConcreteCategory C] {M N K : C} {f : M ⟶ N} [HasCokernel f] {g h : cokernel f ⟶ K} (w : ∀ n : N, g (cokernel.π f n) = h (cokernel.π f n)) : g = h := by
ext x simpa using w x
2
import Mathlib.Geometry.Manifold.MFDeriv.Defs #align_import geometry.manifold.mfderiv from "leanprover-community/mathlib"@"e473c3198bb41f68560cab68a0529c854b618833" noncomputable section open scoped Topology Manifold open Set Bundle section DerivativesProperties variable {𝕜 : Type*} [NontriviallyNormedFiel...
Mathlib/Geometry/Manifold/MFDeriv/Basic.lean
54
59
theorem uniqueMDiffWithinAt_iff {s : Set M} {x : M} : UniqueMDiffWithinAt I s x ↔ UniqueDiffWithinAt 𝕜 ((extChartAt I x).symm ⁻¹' s ∩ (extChartAt I x).target) ((extChartAt I x) x) := by
apply uniqueDiffWithinAt_congr rw [nhdsWithin_inter, nhdsWithin_inter, nhdsWithin_extChartAt_target_eq]
2
import Mathlib.Algebra.Module.Zlattice.Basic import Mathlib.NumberTheory.NumberField.Embeddings import Mathlib.NumberTheory.NumberField.FractionalIdeal #align_import number_theory.number_field.canonical_embedding from "leanprover-community/mathlib"@"60da01b41bbe4206f05d34fd70c8dd7498717a30" variable (K : Type*) [F...
Mathlib/NumberTheory/NumberField/CanonicalEmbedding/Basic.lean
139
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theorem latticeBasis_apply [NumberField K] (i : Free.ChooseBasisIndex ℤ (𝓞 K)) : latticeBasis K i = (canonicalEmbedding K) (integralBasis K i) := by
simp only [latticeBasis, integralBasis_apply, coe_basisOfLinearIndependentOfCardEqFinrank, Function.comp_apply, Equiv.apply_symm_apply]
2
import Mathlib.Topology.PartialHomeomorph import Mathlib.Topology.SeparatedMap #align_import topology.is_locally_homeomorph from "leanprover-community/mathlib"@"e97cf15cd1aec9bd5c193b2ffac5a6dc9118912b" open Topology variable {X Y Z : Type*} [TopologicalSpace X] [TopologicalSpace Y] [TopologicalSpace Z] (g : Y →...
Mathlib/Topology/IsLocalHomeomorph.lean
90
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theorem of_comp_left (hgf : IsLocalHomeomorphOn (g ∘ f) s) (hg : IsLocalHomeomorphOn g (f '' s)) (cont : ∀ x ∈ s, ContinuousAt f x) : IsLocalHomeomorphOn f s := mk f s fun x hx ↦ by obtain ⟨g, hxg, rfl⟩ := hg (f x) ⟨x, hx, rfl⟩ obtain ⟨gf, hgf, he⟩ := hgf x hx refine ⟨(gf.restr <| f ⁻¹' g.source).trans g.symm...
apply interior_subset hy.1.2 rw [← he, g.eq_symm_apply this (by apply g.map_source this), Function.comp_apply]
2
import Mathlib.Algebra.Order.BigOperators.Group.Finset import Mathlib.Data.Nat.Factors import Mathlib.Order.Interval.Finset.Nat #align_import number_theory.divisors from "leanprover-community/mathlib"@"e8638a0fcaf73e4500469f368ef9494e495099b3" open scoped Classical open Finset namespace Nat variable (n : ℕ) d...
Mathlib/NumberTheory/Divisors.lean
79
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theorem mem_properDivisors {m : ℕ} : n ∈ properDivisors m ↔ n ∣ m ∧ n < m := by
rcases eq_or_ne m 0 with (rfl | hm); · simp [properDivisors] simp only [and_comm, ← filter_dvd_eq_properDivisors hm, mem_filter, mem_range]
2
import Mathlib.Analysis.Convex.Hull #align_import analysis.convex.extreme from "leanprover-community/mathlib"@"c5773405394e073885e2a144c9ca14637e8eb963" open Function Set open scoped Classical open Affine variable {𝕜 E F ι : Type*} {π : ι → Type*} section SMul variable (𝕜) [OrderedSemiring 𝕜] [AddCommMonoi...
Mathlib/Analysis/Convex/Extreme.lean
120
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theorem isExtreme_biInter {F : Set (Set E)} (hF : F.Nonempty) (hA : ∀ B ∈ F, IsExtreme 𝕜 A B) : IsExtreme 𝕜 A (⋂ B ∈ F, B) := by
haveI := hF.to_subtype simpa only [iInter_subtype] using isExtreme_iInter fun i : F ↦ hA _ i.2
2
import Mathlib.Analysis.Normed.Group.Hom import Mathlib.Analysis.Normed.Group.Completion #align_import analysis.normed.group.hom_completion from "leanprover-community/mathlib"@"17ef379e997badd73e5eabb4d38f11919ab3c4b3" noncomputable section open Set NormedAddGroupHom UniformSpace section Completion variable {G...
Mathlib/Analysis/Normed/Group/HomCompletion.lean
165
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theorem NormedAddGroupHom.ker_le_ker_completion (f : NormedAddGroupHom G H) : (toCompl.comp <| incl f.ker).range ≤ f.completion.ker := by
rintro _ ⟨⟨g, h₀ : f g = 0⟩, rfl⟩ simp [h₀, mem_ker, Completion.coe_zero]
2
import Mathlib.Analysis.SpecialFunctions.Pow.Real import Mathlib.Data.Int.Log #align_import analysis.special_functions.log.base from "leanprover-community/mathlib"@"f23a09ce6d3f367220dc3cecad6b7eb69eb01690" open Set Filter Function open Topology noncomputable section namespace Real variable {b x y : ℝ} -- @...
Mathlib/Analysis/SpecialFunctions/Log/Base.lean
132
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theorem logb_rpow : logb b (b ^ x) = x := by
rw [logb, div_eq_iff, log_rpow b_pos] exact log_b_ne_zero b_pos b_ne_one
2
import Mathlib.Algebra.Order.Monoid.Defs import Mathlib.Algebra.Order.Sub.Defs import Mathlib.Util.AssertExists #align_import algebra.order.group.defs from "leanprover-community/mathlib"@"b599f4e4e5cf1fbcb4194503671d3d9e569c1fce" open Function universe u variable {α : Type u} class OrderedAddCommGroup (α : Ty...
Mathlib/Algebra/Order/Group/Defs.lean
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theorem lt_inv_mul_iff_mul_lt : b < a⁻¹ * c ↔ a * b < c := by
rw [← mul_lt_mul_iff_left a] simp
2
import Mathlib.RingTheory.FractionalIdeal.Basic import Mathlib.RingTheory.Ideal.Norm namespace FractionalIdeal open scoped Pointwise nonZeroDivisors variable {R : Type*} [CommRing R] [IsDedekindDomain R] [Module.Free ℤ R] [Module.Finite ℤ R] variable {K : Type*} [CommRing K] [Algebra R K] [IsFractionRing R K] th...
Mathlib/RingTheory/FractionalIdeal/Norm.lean
97
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theorem coeIdeal_absNorm (I₀ : Ideal R) : absNorm (I₀ : FractionalIdeal R⁰ K) = Ideal.absNorm I₀ := by
rw [absNorm_eq' 1 I₀ (by rw [one_smul]; rfl), OneMemClass.coe_one, _root_.map_one, abs_one, Int.cast_one, _root_.div_one]
2
import Mathlib.Topology.Algebra.UniformGroup import Mathlib.Topology.UniformSpace.Pi import Mathlib.Data.Matrix.Basic #align_import topology.uniform_space.matrix from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982" open Uniformity Topology variable (m n 𝕜 : Type*) [UniformSpace 𝕜] na...
Mathlib/Topology/UniformSpace/Matrix.lean
37
40
theorem uniformContinuous {β : Type*} [UniformSpace β] {f : β → Matrix m n 𝕜} : UniformContinuous f ↔ ∀ i j, UniformContinuous fun x => f x i j := by
simp only [UniformContinuous, Matrix.uniformity, Filter.tendsto_iInf, Filter.tendsto_comap_iff] apply Iff.intro <;> intro a <;> apply a
2
import Mathlib.Topology.Order.MonotoneContinuity import Mathlib.Topology.Algebra.Order.LiminfLimsup import Mathlib.Topology.Instances.NNReal import Mathlib.Topology.EMetricSpace.Lipschitz import Mathlib.Topology.Metrizable.Basic import Mathlib.Topology.Order.T5 #align_import topology.instances.ennreal from "leanprove...
Mathlib/Topology/Instances/ENNReal.lean
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theorem eventuallyEq_of_toReal_eventuallyEq {l : Filter α} {f g : α → ℝ≥0∞} (hfi : ∀ᶠ x in l, f x ≠ ∞) (hgi : ∀ᶠ x in l, g x ≠ ∞) (hfg : (fun x => (f x).toReal) =ᶠ[l] fun x => (g x).toReal) : f =ᶠ[l] g := by
filter_upwards [hfi, hgi, hfg] with _ hfx hgx _ rwa [← ENNReal.toReal_eq_toReal hfx hgx]
2
import Mathlib.Algebra.GroupPower.IterateHom import Mathlib.Algebra.Polynomial.Eval import Mathlib.GroupTheory.GroupAction.Ring #align_import data.polynomial.derivative from "leanprover-community/mathlib"@"bbeb185db4ccee8ed07dc48449414ebfa39cb821" noncomputable section open Finset open Polynomial namespace Pol...
Mathlib/Algebra/Polynomial/Derivative.lean
86
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theorem derivative_monomial (a : R) (n : ℕ) : derivative (monomial n a) = monomial (n - 1) (a * n) := by
rw [derivative_apply, sum_monomial_index, C_mul_X_pow_eq_monomial] simp
2
import Mathlib.Analysis.MeanInequalities import Mathlib.Analysis.MeanInequalitiesPow import Mathlib.Analysis.SpecialFunctions.Pow.Continuity import Mathlib.Data.Set.Image import Mathlib.Topology.Algebra.Order.LiminfLimsup #align_import analysis.normed_space.lp_space from "leanprover-community/mathlib"@"de83b43717abe3...
Mathlib/Analysis/NormedSpace/lpSpace.lean
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theorem memℓp_zero_iff {f : ∀ i, E i} : Memℓp f 0 ↔ Set.Finite { i | f i ≠ 0 } := by
dsimp [Memℓp] rw [if_pos rfl]
2
import Mathlib.CategoryTheory.Closed.Monoidal import Mathlib.CategoryTheory.Linear.Yoneda import Mathlib.Algebra.Category.ModuleCat.Monoidal.Symmetric #align_import algebra.category.Module.monoidal.closed from "leanprover-community/mathlib"@"74403a3b2551b0970855e14ef5e8fd0d6af1bfc2" suppress_compilation universe ...
Mathlib/Algebra/Category/ModuleCat/Monoidal/Closed.lean
88
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theorem ihom_ev_app (M N : ModuleCat.{u} R) : (ihom.ev M).app N = TensorProduct.uncurry _ _ _ _ LinearMap.id.flip := by
apply TensorProduct.ext' apply ModuleCat.monoidalClosed_uncurry
2
import Mathlib.Data.Finsupp.Encodable import Mathlib.LinearAlgebra.Pi import Mathlib.LinearAlgebra.Span import Mathlib.Data.Set.Countable #align_import linear_algebra.finsupp from "leanprover-community/mathlib"@"9d684a893c52e1d6692a504a118bfccbae04feeb" noncomputable section open Set LinearMap Submodule namespa...
Mathlib/LinearAlgebra/Finsupp.lean
255
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theorem iInf_ker_lapply_le_bot : ⨅ a, ker (lapply a : (α →₀ M) →ₗ[R] M) ≤ ⊥ := by
simp only [SetLike.le_def, mem_iInf, mem_ker, mem_bot, lapply_apply] exact fun a h => Finsupp.ext h
2
import Mathlib.Algebra.GroupWithZero.Divisibility import Mathlib.Algebra.Ring.Divisibility.Basic import Mathlib.Algebra.Ring.Hom.Defs import Mathlib.GroupTheory.GroupAction.Units import Mathlib.Logic.Basic import Mathlib.Tactic.Ring #align_import ring_theory.coprime.basic from "leanprover-community/mathlib"@"a95b16cb...
Mathlib/RingTheory/Coprime/Basic.lean
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theorem IsCoprime.mul_right (H1 : IsCoprime x y) (H2 : IsCoprime x z) : IsCoprime x (y * z) := by
rw [isCoprime_comm] at H1 H2 ⊢ exact H1.mul_left H2
2
import Mathlib.Analysis.SpecificLimits.Basic import Mathlib.Data.Setoid.Basic import Mathlib.Dynamics.FixedPoints.Topology import Mathlib.Topology.MetricSpace.Lipschitz #align_import topology.metric_space.contracting from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982" open scoped Classi...
Mathlib/Topology/MetricSpace/Contracting.lean
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theorem one_sub_K_ne_top : (1 : ℝ≥0∞) - K ≠ ∞ := by
norm_cast exact ENNReal.coe_ne_top
2
import Mathlib.Probability.Notation import Mathlib.Probability.Density import Mathlib.Probability.ConditionalProbability import Mathlib.Probability.ProbabilityMassFunction.Constructions open scoped Classical MeasureTheory NNReal ENNReal -- TODO: We can't `open ProbabilityTheory` without opening the `ProbabilityThe...
Mathlib/Probability/Distributions/Uniform.lean
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theorem toMeasurable_iff {X : Ω → E} {s : Set E} : IsUniform X (toMeasurable μ s) ℙ μ ↔ IsUniform X s ℙ μ := by
unfold IsUniform rw [ProbabilityTheory.cond_toMeasurable_eq]
2
import Mathlib.Data.Set.Image import Mathlib.Data.SProd #align_import data.set.prod from "leanprover-community/mathlib"@"48fb5b5280e7c81672afc9524185ae994553ebf4" open Function namespace Set section Prod variable {α β γ δ : Type*} {s s₁ s₂ : Set α} {t t₁ t₂ : Set β} {a : α} {b : β} theorem Subsingleton.pro...
Mathlib/Data/Set/Prod.lean
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theorem prod_empty : s ×ˢ (∅ : Set β) = ∅ := by
ext exact and_false_iff _
2
import Mathlib.Data.Finset.Lattice #align_import data.finset.pairwise from "leanprover-community/mathlib"@"c4c2ed622f43768eff32608d4a0f8a6cec1c047d" open Finset variable {α ι ι' : Type*} instance [DecidableEq α] {r : α → α → Prop} [DecidableRel r] {s : Finset α} : Decidable ((s : Set α).Pairwise r) := dec...
Mathlib/Data/Finset/Pairwise.lean
27
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theorem Finset.pairwiseDisjoint_range_singleton : (Set.range (singleton : α → Finset α)).PairwiseDisjoint id := by
rintro _ ⟨a, rfl⟩ _ ⟨b, rfl⟩ h exact disjoint_singleton.2 (ne_of_apply_ne _ h)
2
import Mathlib.Algebra.Group.Center #align_import group_theory.subsemigroup.centralizer from "leanprover-community/mathlib"@"cc67cd75b4e54191e13c2e8d722289a89e67e4fa" variable {M : Type*} {S T : Set M} namespace Set variable (S) @[to_additive addCentralizer " The centralizer of a subset of an additive magma. ...
Mathlib/Algebra/Group/Centralizer.lean
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theorem div_mem_centralizer₀ [GroupWithZero M] (ha : a ∈ centralizer S) (hb : b ∈ centralizer S) : a / b ∈ centralizer S := by
rw [div_eq_mul_inv] exact mul_mem_centralizer ha (inv_mem_centralizer₀ hb)
2
import Mathlib.Data.Set.Pairwise.Basic import Mathlib.Data.Set.Lattice import Mathlib.Data.SetLike.Basic #align_import order.chain from "leanprover-community/mathlib"@"c227d107bbada5d0d9d20287e3282c0a7f1651a0" open scoped Classical open Set variable {α β : Type*} section Chain variable (r : α → α → Prop) ...
Mathlib/Order/Chain.lean
171
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theorem succChain_spec (h : ∃ t, IsChain r s ∧ SuperChain r s t) : SuperChain r s (SuccChain r s) := by
have : IsChain r s ∧ SuperChain r s h.choose := h.choose_spec simpa [SuccChain, dif_pos, exists_and_left.mp h] using this.2
2
import Mathlib.Geometry.Manifold.MFDeriv.Basic noncomputable section open scoped Manifold variable {𝕜 : Type*} [NontriviallyNormedField 𝕜] {E : Type*} [NormedAddCommGroup E] [NormedSpace 𝕜 E] {E' : Type*} [NormedAddCommGroup E'] [NormedSpace 𝕜 E'] {f : E → E'} {s : Set E} {x : E} section MFDerivFderiv t...
Mathlib/Geometry/Manifold/MFDeriv/FDeriv.lean
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theorem hasMFDerivWithinAt_iff_hasFDerivWithinAt {f'} : HasMFDerivWithinAt 𝓘(𝕜, E) 𝓘(𝕜, E') f s x f' ↔ HasFDerivWithinAt f f' s x := by
simpa only [HasMFDerivWithinAt, and_iff_right_iff_imp, mfld_simps] using HasFDerivWithinAt.continuousWithinAt
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import Mathlib.Analysis.SpecialFunctions.Pow.Real import Mathlib.Data.Int.Log #align_import analysis.special_functions.log.base from "leanprover-community/mathlib"@"f23a09ce6d3f367220dc3cecad6b7eb69eb01690" open Set Filter Function open Topology noncomputable section namespace Real variable {b x y : ℝ} -- @...
Mathlib/Analysis/SpecialFunctions/Log/Base.lean
105
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theorem mul_logb {a b c : ℝ} (h₁ : b ≠ 0) (h₂ : b ≠ 1) (h₃ : b ≠ -1) : logb a b * logb b c = logb a c := by
unfold logb rw [mul_comm, div_mul_div_cancel _ (log_ne_zero.mpr ⟨h₁, h₂, h₃⟩)]
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import Mathlib.RingTheory.Localization.FractionRing import Mathlib.Algebra.Polynomial.RingDivision #align_import field_theory.ratfunc from "leanprover-community/mathlib"@"bf9bbbcf0c1c1ead18280b0d010e417b10abb1b6" noncomputable section open scoped Classical open scoped nonZeroDivisors Polynomial universe u v va...
Mathlib/FieldTheory/RatFunc/Defs.lean
123
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theorem liftOn_ofFractionRing_mk {P : Sort v} (n : K[X]) (d : K[X]⁰) (f : K[X] → K[X] → P) (H : ∀ {p q p' q'} (_hq : q ∈ K[X]⁰) (_hq' : q' ∈ K[X]⁰), q' * p = q * p' → f p q = f p' q') : RatFunc.liftOn (ofFractionRing (Localization.mk n d)) f @H = f n d := by
rw [RatFunc.liftOn] exact Localization.liftOn_mk _ _ _ _
2
import Mathlib.Analysis.Convex.Function import Mathlib.Analysis.Convex.StrictConvexSpace import Mathlib.MeasureTheory.Function.AEEqOfIntegral import Mathlib.MeasureTheory.Integral.Average #align_import analysis.convex.integral from "leanprover-community/mathlib"@"f2ce6086713c78a7f880485f7917ea547a215982" open Mea...
Mathlib/Analysis/Convex/Integral.lean
122
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theorem ConcaveOn.average_mem_hypograph [IsFiniteMeasure μ] [NeZero μ] (hg : ConcaveOn ℝ s g) (hgc : ContinuousOn g s) (hsc : IsClosed s) (hfs : ∀ᵐ x ∂μ, f x ∈ s) (hfi : Integrable f μ) (hgi : Integrable (g ∘ f) μ) : (⨍ x, f x ∂μ, ⨍ x, g (f x) ∂μ) ∈ {p : E × ℝ | p.1 ∈ s ∧ p.2 ≤ g p.1} := by
simpa only [mem_setOf_eq, Pi.neg_apply, average_neg, neg_le_neg_iff] using hg.neg.average_mem_epigraph hgc.neg hsc hfs hfi hgi.neg
2
import Mathlib.Topology.Connected.Basic import Mathlib.Topology.Separation open scoped Topology variable {X Y A} [TopologicalSpace X] [TopologicalSpace A] theorem embedding_toPullbackDiag (f : X → Y) : Embedding (toPullbackDiag f) := Embedding.mk' _ (injective_toPullbackDiag f) fun x ↦ by rw [toPullbackDiag,...
Mathlib/Topology/SeparatedMap.lean
89
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theorem isSeparatedMap_iff_closedEmbedding {f : X → Y} : IsSeparatedMap f ↔ ClosedEmbedding (toPullbackDiag f) := by
rw [isSeparatedMap_iff_isClosed_diagonal, ← range_toPullbackDiag] exact ⟨fun h ↦ ⟨embedding_toPullbackDiag f, h⟩, fun h ↦ h.isClosed_range⟩
2
import Mathlib.Topology.MetricSpace.HausdorffDistance #align_import topology.metric_space.pi_nat from "leanprover-community/mathlib"@"49b7f94aab3a3bdca1f9f34c5d818afb253b3993" noncomputable section open scoped Classical open Topology Filter open TopologicalSpace Set Metric Filter Function attribute [local simp...
Mathlib/Topology/MetricSpace/PiNat.lean
74
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theorem apply_firstDiff_ne {x y : ∀ n, E n} (h : x ≠ y) : x (firstDiff x y) ≠ y (firstDiff x y) := by
rw [firstDiff_def, dif_pos h] exact Nat.find_spec (ne_iff.1 h)
2