2.

(a) Sketch a graph of the set

{(x, y) : x2 + 2y2 < 6, y ~ O}

and decide whether this set is relatively open or relatively closed in the subspace {(x, y) : y ~ O}. Do the same for the subspace {(x, y) : x2 + 2y2 <

6}. Explain your answers.

(b) Sketch a graph of the set and decide whether this set is relatively open or relatively closed in the subspace Bl (0,0). Do the same for the subspace Bv'2(2,0). Explain your answers.