3. 6 points For a given r > 0, define Br = {x E R" , (|x||

3. 6 points For a given r > 0, define Br {x e IRn , r}, the ball of radius r centere at the origin. a. Express Br as the intersection of an infinite number of half spaces. b. Can one express Br as the intersection of a finite number of half spaces? Explain your answer in the two dimensional (R2) case, by drawing relevant figures. (Your answer for this problem does not have to be rigorous. For example, a convincing figure and explanation of it would be sufficient. )