[Discrete Mathematics Algebra System

The basic properties of an algebraic system

basic requirements:

  • Composite function definition - the definition of the operation to meet the unique mapping
  • Closed

1 relates to a binary operation

Commutative law

Associativity left and the right combination of binding  proof does not satisfy the associative law only to find counter-examples

Idempotent law

Erasing law        

2 relates to two different binary operations

Distributive property (binary operation), the left and the right dispensing assigned

eg <X, *, +>, * + to meet the distributive property, then there should be:

Any x1, x2, x3 belonging to X,

Left assignment: x1 * (x2 + x3) = x1 * x2 + x1 * x3

&&

Right distribution: (x2 + x3) * x1 = x2 * x1 + x3 * x1        

or prove that only one side, again proved the establishment of exchange law

Absorption law - for two commutative operations

Specific elements of the binary operation 3

Yuan Yuan && unitary unitary left and right identity element

Zero dollars left and right zero dollars zero dollars &&

Idempotents  operation table as an element corresponding to the diagonal elements called columns Idempotents

Yuan Yuan and its inverse reversible

Second, isomorphism & homomorphism

  • Solving isomorphism / homomorphism between two algebraic system
  • Determining whether a function is isomorphic (same state) between the two algebraic system
    • F is a homomorphism proved の step V1 to V2:
      •  Analyzing two algebraic system is not the same type of
      • F is the same see whether the domain of the V1 domain, and if f is a subset of the range of the V2 domain
      • Determining whether all elements meet arithmetic operation as equal as
    • F is an isomorphism proved の step V1 to V2:
      •  Analyzing two algebraic system is not the same type of
      • See f is not bijective, f is the same whether the V1 domain of the domain, and if f is the same range as defined V2 domain
      • Determining whether all elements meet arithmetic operation as equal as

 

Known systems of the same type of algebraic S1 = <U, +> S2 = <V, *>, and mapping f: U-> V

The same type of algebraic system

Bijection can define a set of two operations on the same corresponding to each image point of the original image and calculating the number of cells

Algebraic System homomorphic

f(u1+u2) = f(u1)*f(u2)

Homogeneous algebraic system

and f is a bijection f (u1 + u2) = f (u1) * f (u2)

Depending on the type of f, a different mapping may be generated:

  • f is surjective, f is the algebraic system between two full homomorphism
  • f is injective, f is the algebraic system between two single homomorphism
  • f is injective , and the same two algebraic system, f is the algebraic system between two endomorphism
  • f is a bijection f is between two algebraic systems isomorphism
  • f is bijective, and the same number of two generations of systems, f is the algebraic system between two self-isomorphism

 

Product algebraic S1xS2 = <UxV, #>, for any <u, v> <uu, vv> belongs UxV, <u, v> # <uu, vv> = <u + uu, v * vv>

........... small n-algebraic system may generate large algebraic system

 

Congruence

Given <S, *>, E is the equivalence relation S, E * have substitution on the nature, i.e.,

Any x, xx, y, yy belonging to S, wherein x, xx in an equivalence class (xExx), y, yy at an equivalence class (yEyy),

Then x * y and xx * yy in an equivalence class ((x * y) E (xx * yy))

The remaining relations of gender quality:

It can be induced from a relationship with any remainder of a homomorphism

 

QUOTIENT: an algebraic system may generate large number of small ~ algebraic system operation equivalence classes of equivalence classes equals operator

 

Quotient algebra of gender quality:

An algebraic system and its algebras homomorphism, and may be configured from the operational to the natural homomorphism the number of Shang g (x) = [x] _R

 

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