The set of separating hyperplanes. Suppose that C and D are disjoint subsets of Rn. Consider the set of (a,b)∈Rn+1 for which aTx≤b for all x∈C, and aTx≥b for all x∈D. Show that this set is a convex cone (which is the singleton {0} if there is no hyperplane that separates C and D).