Matrices: The Basics of Linear Algebra

In the previous section, you learnt about linear transformations. We will now move on to matrices, a time-tested and powerful tool used to perform calculations involving linear combinations. 

Let’s try and recall some basics of matrices.

A matrix is a collection of values divided into rows and columns. For the scope of this module, we will be dealing with matrices where all values will be numerical.

$A=\left[\begin{array}{ccc}2& 4& 6\\ 1& 5& 9\end{array}\right]$

Below, we will list down a glossary of terms that will help you revisit concepts

Rows: Rows are horizontal. The above matrix A has 2 rows

Columns: Columns are vertical. The above matrix A has 3 columns. 

Dimensions: The number of rows and columns. For m rows and n columns, they are mxn. The dimensions of the above matrix A are 2x3

Square Matrices: These are matrices where number of rows is equal to number of column. The above matrix A is not a square matrix.

Let's now move to operations performed on matrices.

Additional Reading

1. An intro video to matrices