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Theorems · Theorem · commutative algebra

RingHom.comap_ker

∀ {R : Type u} {S : Type v} {T : Type w} [inst : Semiring R] [inst_1 : Semiring S] [inst_2 : Semiring T] (f : S →+* R)
  (g : T →+* S), Ideal.comap g (RingHom.ker f) = RingHom.ker (f.comp g)
Defined in
Mathlib.RingTheory.Ideal.Maps
Cited by
16 results in Mathlib
Foundations
Depth 20 from the axioms · uses propext, Quot.sound
Assumes
SemiringSemiringSemiring

Around this declaration

Dashed lines are statement dependencies; solid lines are citations in proofs.

AlgebraicGeometry.Scheme.Hom.ker_apply · cited by 14Hom.ker_applyAlgebraicGeometry.Scheme.Hom.support_ker · cited by 6Hom.support_kerAlgebraicGeometry.Scheme.Hom.le_ker_comp · cited by 5Hom.le_ker_compRingHom.ker_equiv_comp · cited by 3RingHom.ker_equiv_compRingHom.ker_comp_of_injective · cited by 3RingHom.ker_comp_of_injec…AlgHom.comap_ker · cited by 2AlgHom.comap_kerIdeal.ker_quotientMap_mk · cited by 1Ideal.ker_quotientMap_mkAlgebra.Extension.cotangentComplex_comp_h1CotangentEquivCotangent · cited by 1Extension.cotangentComple…Polynomial.UniversalCoprimeFactorizationRing.exists_liesOver_residueFieldMap_bijective · cited by 1UniversalCoprimeFactoriza…Algebra.TensorProduct.map_ker · cited by 1TensorProduct.map_kerAlgebraicGeometry.Scheme.ker_of_isAffine · cited by 1Scheme.ker_of_isAffineAlgebraicGeometry.Scheme.IdealSheafData.ker_glueDataObjι_appTop · cited by 1IdealSheafData.ker_glueDa…RingHom.FinitePresentation.polynomial_induction · cited by 1FinitePresentation.polyno…Algebra.Generators.ker_localizationAway · cited by 1Generators.ker_localizati…IsLocalization.Away.of_surjective_of_isScalarTower · cited by 0Away.of_surjective_of_isS…Semiring · cited by 13802SemiringRingHom · cited by 10189RingHomIdeal · cited by 4748IdealBot.bot · cited by 4720Bot.botRingHom.comp · cited by 899RingHom.compIdeal.comap · cited by 443Ideal.comapRingHom.ker · cited by 363RingHom.kerIdeal.comap_comap · cited by 27Ideal.comap_comapRingHom.ker_eq_comap_bot · cited by 23RingHom.ker_eq_comap_botRingHom.comap_kerCITED BYCITES

Cites9

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Cited by16

Results whose statement or proof uses this declaration.