Powered by Blogger.
Welcome to online portal for learning pure mathematics.

Definition of Vector Space


Let F be an orbitrary field then a non-empty set V is called a 
vector    space over the field F written as V(F) if following axioms are satisfied-
❶-There is defined an internal composition in V to be denoted additively such that (V,+) is an abelian group.
i.e.
1-Closure axiom:-
If α,β єV  then
α+βєV, ∀ α,βєBV

2-Associative law:-
If α,β,γєV then
α+(β+γ)=(α+β)+γ,∀α,β,γєV
3-Identity Element:-
There Exist 0єV such that
α+0=0+α, ∀αєV
4-Inverse  axiom:-
Corresponding to each αєV there exist –αєV  such that
α+(-α)=(-α)+α=0, ∀αєV
5-commutative Law:-
If α+β=β+α, ∀ αєV

❷-There is defined an internal composition in V over F,called
scalar multiplication,i.e.
aєF,αєV͢→aαєV, ∀ aєF,αєV

❸-The two composition that is addition on V and scalar multiplication on V(F) satisfies following postulates-
१-a(α+β)=aα+bβ, ∀ α,βєV,aєF
२-(a+b)α=aα+bα,  ∀ αєV, a,bєF
३-(ab)α=a(bα),   ∀ a,bєF, αєV
४-1.α=α,  ∀ αєV and I is the unity element of F

Note-
❶-If F is a field of real number then V is called real vector space and is written as V(R).If F is a field of rational number or complex number then v is called rational vector space or Complex vector space.
❷-The  element of V are called vectors and elements of F as scalars.Here the word vector is not a physical quantity which have magnitude and direction,these are only elements of V.
❸-Vector space is also called as Linear space.
❹-In a vector space we deals with four composition two internal composition in the field F,one internal composition in V and one external composition in V(F).   

  • Digg
  • Del.icio.us
  • StumbleUpon
  • Reddit
  • RSS

0 comments:

Post a Comment