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Theorems · Theorem · commutative algebra

Ideal.Quotient.ringHom_ext

∀ {R : Type u} [inst : Ring R] {I : Ideal R} {S : Type v} [inst_1 : I.IsTwoSided] [inst_2 : NonAssocSemiring S]
  ⦃f g : R ⧸ I →+* S⦄, f.comp (Ideal.Quotient.mk I) = g.comp (Ideal.Quotient.mk I) → f = g

Two RingHoms from the quotient by an ideal are equal if their compositions with Ideal.Quotient.mk' are equal. See note [partially-applied ext lemmas].

Defined in
Mathlib.RingTheory.Ideal.Quotient.Defs
Cited by
17 results in Mathlib
Foundations
Depth 83 from the axioms · uses propext, Classical.choice, Quot.sound
Assumes
RingIdeal.IsTwoSidedNonAssocSemiring

Around this declaration

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

Ideal.Quotient.factor_eq · cited by 5Quotient.factor_eqRing.DirectLimit.hom_ext · cited by 5DirectLimit.hom_extIsLocalRing.ResidueField.map_comp · cited by 3ResidueField.map_compIsLocalRing.ResidueField.map_id · cited by 3ResidueField.map_idAdjoinRoot.ringHom_ext · cited by 3AdjoinRoot.ringHom_extIdeal.ResidueField.ringHom_ext · cited by 3ResidueField.ringHom_extNumberField.InfinitePlace.inertiaDeg_eq_finrank · cited by 2InfinitePlace.inertiaDeg_…Ideal.card_stabilizer_eq_card_inertia_mul_finrank · cited by 2Ideal.card_stabilizer_eq_…NumberField.Ideal.inertiaDeg_primesOverSpanEquivMonicFactorsMod_symm_apply · cited by 1Ideal.inertiaDeg_primesOv…Ideal.Quotient.factor_comp · cited by 1Quotient.factor_compIsLocalization.AtPrime.inertiaDeg_map_eq_inertiaDeg · cited by 1AtPrime.inertiaDeg_map_eq…trace_quotient_eq_trace_localization_quotient · cited by 1trace_quotient_eq_trace_l…Ideal.fst_comp_quotientInfEquivQuotientProd · cited by 0Ideal.fst_comp_quotientIn…Ideal.fst_comp_quotientMulEquivQuotientProd · cited by 0Ideal.fst_comp_quotientMu…Ideal.Quotient.ringHom_ext_iff · cited by 0Quotient.ringHom_ext_iffRingHom · cited by 10189RingHomRing · cited by 7463RingIdeal · cited by 4748IdealHasQuotient.Quotient · cited by 2301HasQuotient.QuotientRingHom.comp · cited by 899RingHom.compNonAssocSemiring · cited by 805NonAssocSemiringIdeal.Quotient.mk · cited by 610Quotient.mkRingHom.ext · cited by 331RingHom.extIdeal.IsTwoSided · cited by 179Ideal.IsTwoSidedQuotient.inductionOn' · cited by 69Quotient.inductionOn'RingHom.congr_fun · cited by 29RingHom.congr_funQuotient.ringHom_extCITED BYCITES

Cites11

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Cited by17

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