is nonsingular. Show that f is invertible and that f −1 is a linear-fractional mapping. Give an explicit expression for f−1 and its domain in terms of A, b, c, and d. Hint. It may be easier to express f −1 in terms of Q.
2.19 Linear-fractional functions and convex sets. Let f : Rm → Rn be the linear-fractional function
In this problem we study the inverse image of a convex set C under f, i.e.,
For each of the following sets C ⊆ Rn, give a simple ...