Names for Matrices

If you sometimes forget whether rows or columns come first, just remember that matrices are build out of rowman columns. A matrix can be given a name. In printed text, the name for a matrix is usually a capital letter in bold face, like A or M. Sometimes as a reminder the dimensions are written to the right of the letter, as in B_3x3.

The elements of a matrix also have names, usually a lowercase letter the same as the matrix name, with the position of the element written as a subscript. So, for example, the 3x3 matrix A might be written as:

Sometimes you write A = [a_ij] to say that the elements of matrix A are named a_ij.