THIS is emphatically a text-book, deductive in method and Euclidean in arrangement; as such, it has the defects of its qualities, but its merits are undeniable. In this volume the author deals with ...

In this study we analyze students' understanding of two-variable function; in particular we consider their understanding of domain, possible arbitrary nature of function assignment, uniqueness of ...

The operator convex functions of several variables are characterized in terms of a non-commutative generalization of Jensen's inequality, extending previous results of F. Hansen and G.K. Pedersen for ...

Functions of two variables can be visualized in many ways: heat maps in 2D, contour curves in 2D, wireframes in 3D, surfaces in 3D. We begin by defining a function of two variables, building an array ...