# Math Help - Determine whether W is a subspace of the vector space?

1. ## Determine whether W is a subspace of the vector space?

W={(x,y): y=ax, a is an integer}, V=R^(2)

It is not a subspace of V, but I can't find an example, where this is not valid.

2. ## Re: Determine whether W is a subspace of the vector space?

Originally Posted by Jav
W={(x,y): y=ax, a is an integer}, V=R^(2)

It is not a subspace of V, but I can't find an example, where this is not valid.

$(1,2) \in W, (1,3)\in W$. But does $\frac12(1,2)+\frac12(1,3)$?