Convex Sets - Intersection

Question

The question we had to complete was: Choose two points in the set whose line segment joining them is not in the set. For the question that I have posted, why is my answer (-sqrt(3),2),(sqrt(3),2) Not correct?

Answer 1

No. If $(x,y) = ( \pm \sqrt{3},2)$, then $x^2=3$ and $y^2=4$, hence $(x,y) \notin T$.