In this appendix, we summarize key definitions and relations in vector calculus. Some of these (i.e., the gradient and the Laplacian in Cartesian coordinates) have already been briefly introduced in Appendix A, Section A.6, but we give a uniform and extended set of definitions here.
C.1 Vector calculus operators
Del or nabla operator
In vector calculus, it is convenient to think of the operator, known as del or nabla, as
This gives a useful shorthand for writing down the other important vector calculus ...