EDB — 19C

Exercises

1. [19C] Let \(C⊂ ℝ^ n\) be a convex, \(f:C→ℝ\) a convex function, and \(r∈ℝ\): then \(\{ x∈ C,f(x){\lt}r\} \) and \(\{ x∈ C,f(x)≤ r\} \) are convex (possibly empty) sets.