Question: May a vector space have more than one zero vector?justify. Let v=(a1,a2):a1,a2∈R. for (a1,a2) , (b1,b2) = (a1+2b1,a2+3b2) and c(a1,a2) = (ca1,a2) .Is v a vector space over f with these operations? justify your answer.
Solution:
Let a vector space have two zeros say 0 and 0^’. From $v_{s3}$ 0 is the identity under addition
Hence ∀x∈V
x + 0 = 0 + x = x…………(1)
also from $v_{s3}$ 0’ is identity under addition.
x + 0’ = 0’ + x = x……….(2)
From (1) and (2)
x + 0 = x + 0′ = x .
Hence there is unique zeros in vector space.
Second part
Here given
v = (a1,a2):a1,a2∈R for (a1,a2), (b1,b2)∈V and c∈R
Define (a1,a2)+(b1,b2)=(a1+2b1,a2+3b2) and c(a1,a2)=(ca1,a2)
Vs1: for (a1,a2),(b1,b2)∈V
(a1,a2)+(b1,b2)=(a1+2a2,b1+3b2)≠(a2+2a1,b2+3b1)≠(b1,b2)+(a1,a2)
Vs1 does not hold.
Vs2: for (a1,a2),(b1,b2)∈V and (c1,c2)∈V
[(a1,a2)+(b1,b2)]+(c1,c2)=[a1+2b1,a2+3b2]+(c1,c2)≠
(a1+2b1+c1,a2+3b2+3b3)≠(a1,a2)+[b1+2c1,b2+3c2]≠(a1,b2)+[(b1,b2)+(c1,c2)]
Vs2 does not hold.
Vs3:if there exist a element z = (d1,d2)∈V such that (a1,a2)+(d1,d2)=(a1,a2)
(a1+2d1,a2+3d2)=(a1,a2)
a1+2d1=a1⇒d1=0
a2+3d2=a2⇒d2=0
This show that (a1,a2)+(0,0)=(a1,a2)
vs4:Let ∀(a1,b1)∃(−a1,−a2)∈V
such that (a1,a2)+(−a1,−a2)=[a1+(−2a1),a2+(−3a2)]=(−a1,−2a2)≠(0,0).
Hence vs4 does not satisfy.
Vs5:1∈F 1.(a1,b1)=(1.a1,b1)=(a1,b1)
Vs6:∀x,y∈F xy(a1,b1)=x(ya1,b)=x[y(a1,b1)]
Vs7:∀x,y∈F (x+y)(a1,b1)=[(x+y)a1,b1]=(xa1+ya1,b1)
also x(a1,b1)+y(a1,b2)=(xa1,b1)+(ya1,b1)=(xa1+ya1,b1+b2)=(xa1+ya1,2b1)
(x+y)(a1,b1)≠x(a1,b1)+y(a1,b1)
Hence vs7 does not satisfy.
Vs8: ∀x∈F x[(a1,b1)+(a2,b2)]=x(a1,b1)+x(a2,b2) = (xa1,b1)+(xa2,b2)
All the condition of vector space does not satisfy hence it is not vector space.
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