Question

W2={(x,y)\epsilon R^2 / x^2 +y^2 \leq 1} ,
is W2 a vector subspace? @MIT 18.06 Linear …

Answer 1

not definitely not, just take \[\vec{v}=(0,1)\] that is inside the circle, but \[2\vec{v}\] is not there, so the circle is not a subspace, in your question is better to change \in instead of epsilon