Consider the following function f(x,y) = |y|
a) graph the worse set of the function at the point (1,3)
b) graph the better set of the function at the point (1,3)
c) Prove that for any generic point (x';y') the worse set is a
convex set. Explain why this implies f (x,y)
is a quasi convex function.
Hint: You will need to use the triangle inequality:
|a+b| ≤ |a|+|b|