- #1
kesun
- 37
- 0
I guess this kind of topic should belong here. :|
My understanding of the subspace still isn't solid enough, so I want to know what I know so far is at least correct.
By definition, a set of vectors S of Rn is called a subspace of Rn iff for all vectors (I will call them x):
1) (x+y) [tex]\in[/tex] S and
2) kx [tex]\in[/tex] S.
Also, the solution set of a homogeneous system is always a subspace.
When I encounter problems such as determine whether or not {(x1,x2,x3)|x1x2=0} is a subspace of its corresponding Rn, I would approach this problem as such:
Since the set has only three vectors, then it's in R3, first of all; then I check for 1): Suppose a set of vectors Y {(y1,y2,y3)|y1y2=0}, then (S+Y)=x1x2+y1y2=0+0=0; for 2): kS=(kx1)(kx2)=(k0)(k0)=0. Therefore it is a subspace of R3.
Is my way of solving this problem correct?
My understanding of the subspace still isn't solid enough, so I want to know what I know so far is at least correct.
By definition, a set of vectors S of Rn is called a subspace of Rn iff for all vectors (I will call them x):
1) (x+y) [tex]\in[/tex] S and
2) kx [tex]\in[/tex] S.
Also, the solution set of a homogeneous system is always a subspace.
When I encounter problems such as determine whether or not {(x1,x2,x3)|x1x2=0} is a subspace of its corresponding Rn, I would approach this problem as such:
Since the set has only three vectors, then it's in R3, first of all; then I check for 1): Suppose a set of vectors Y {(y1,y2,y3)|y1y2=0}, then (S+Y)=x1x2+y1y2=0+0=0; for 2): kS=(kx1)(kx2)=(k0)(k0)=0. Therefore it is a subspace of R3.
Is my way of solving this problem correct?