a. Consider d on R, the real line, to be d(x,y) =
|x2 – y2|. Show that d is NOT a metric on R.
b.Consider d on R, the real line, to be d(x,y) =
|x3 – y3|. Show that d is a metric on R.
2. Let d on R be d(x,y) = |x-y|. The “usual”
distance. Show the interval (-2,7) is an open set.
Note: you must show that any point z
in the interval has...