This paper examines properties and interrelations of several concepts of generalized concavity. It shows that the class of functions that are both 'generalized concave' and 'generalized convex' is ...

We compare and contrast concave and convex lenses by drawing ray diagrams. In this Closer Look segment on Lenses, we compare and contrast concave and convex lenses by drawing ray diagrams and ...

Abstract. As one of the main results we prove that if 𝑓 has Lagrange unique property then 𝑓 is strictly convex or concave (we do not assume continuity of the derivative), Theorem 2.1. We give two ...