{-# OPTIONS --safe --warning=error --without-K #-} open import LogicalFormulae open import Groups.Definition open import Rings.Definition open import Rings.IntegralDomains.Definition open import Setoids.Setoids open import Sets.EquivalenceRelations module Fields.FieldOfFractions.Ring {a b : _} {A : Set a} {S : Setoid {a} {b} A} {_+_ : A → A → A} {_*_ : A → A → A} {R : Ring S _+_ _*_} (I : IntegralDomain R) where open import Fields.FieldOfFractions.Setoid I open import Fields.FieldOfFractions.Addition I open import Fields.FieldOfFractions.Group I open import Fields.FieldOfFractions.Multiplication I fieldOfFractionsRing : Ring fieldOfFractionsSetoid fieldOfFractionsPlus fieldOfFractionsTimes Ring.additiveGroup fieldOfFractionsRing = fieldOfFractionsGroup Ring.*WellDefined fieldOfFractionsRing {a} {b} {c} {d} = fieldOfFractionsTimesWellDefined {a} {b} {c} {d} Ring.1R fieldOfFractionsRing = Ring.1R R ,, (Ring.1R R , IntegralDomain.nontrivial I) Ring.groupIsAbelian fieldOfFractionsRing {a ,, (b , _)} {c ,, (d , _)} = need where open Setoid S open Equivalence eq need : (((a * d) + (b * c)) * (d * b)) ∼ ((b * d) * ((c * b) + (d * a))) need = transitive (Ring.*Commutative R) (Ring.*WellDefined R (Ring.*Commutative R) (transitive (Group.+WellDefined (Ring.additiveGroup R) (Ring.*Commutative R) (Ring.*Commutative R)) (Ring.groupIsAbelian R))) Ring.*Associative fieldOfFractionsRing {a ,, (b , _)} {c ,, (d , _)} {e ,, (f , _)} = need where open Setoid S open Equivalence eq need : ((a * (c * e)) * ((b * d) * f)) ∼ ((b * (d * f)) * ((a * c) * e)) need = transitive (Ring.*WellDefined R (Ring.*Associative R) (symmetric (Ring.*Associative R))) (Ring.*Commutative R) Ring.*Commutative fieldOfFractionsRing {a ,, (b , _)} {c ,, (d , _)} = need where open Setoid S open Equivalence eq need : ((a * c) * (d * b)) ∼ ((b * d) * (c * a)) need = transitive (Ring.*Commutative R) (Ring.*WellDefined R (Ring.*Commutative R) (Ring.*Commutative R)) Ring.*DistributesOver+ fieldOfFractionsRing {a ,, (b , _)} {c ,, (d , _)} {e ,, (f , _)} = need where open Setoid S open Ring R open Equivalence eq inter : b * (a * ((c * f) + (d * e))) ∼ (((a * c) * (b * f)) + ((b * d) * (a * e))) inter = transitive *Associative (transitive *DistributesOver+ (Group.+WellDefined additiveGroup (transitive *Associative (transitive (*WellDefined (transitive (*WellDefined (*Commutative) reflexive) (transitive (symmetric *Associative) (transitive (*WellDefined reflexive *Commutative) *Associative))) reflexive) (symmetric *Associative))) (transitive *Associative (transitive (*WellDefined (transitive (symmetric *Associative) (transitive (*WellDefined reflexive *Commutative) *Associative)) reflexive) (symmetric *Associative))))) need : ((a * ((c * f) + (d * e))) * ((b * d) * (b * f))) ∼ ((b * (d * f)) * (((a * c) * (b * f)) + ((b * d) * (a * e)))) need = transitive (Ring.*WellDefined R reflexive (Ring.*WellDefined R reflexive (Ring.*Commutative R))) (transitive (Ring.*WellDefined R reflexive (Ring.*Associative R)) (transitive (Ring.*Commutative R) (transitive (Ring.*WellDefined R (Ring.*WellDefined R (symmetric (Ring.*Associative R)) reflexive) reflexive) (transitive (symmetric (Ring.*Associative R)) (Ring.*WellDefined R reflexive inter))))) Ring.identIsIdent fieldOfFractionsRing {a ,, (b , _)} = need where open Setoid S open Equivalence eq need : (((Ring.1R R) * a) * b) ∼ (((Ring.1R R * b)) * a) need = transitive (Ring.*WellDefined R (Ring.identIsIdent R) reflexive) (transitive (Ring.*Commutative R) (Ring.*WellDefined R (symmetric (Ring.identIsIdent R)) reflexive))