Ellie's+Matrices

== Matrices with only one column or row are called row or column vectors. The simple defination of a matrix is a rectangular array of numbers, that can be added subtracted, times and divided by eachother. The numbers and contents of a matrix are called either its entries or elements. Letters can also be used in matrices. The following are all examples of intresting matrices: 

**||~ Symmetric ||~ Diagonal ||~ Upper Triangular ||~ Lower Triangular ||~ Zero ||~ Identity || ||** 









 **Facts about matrices; Matrices are two dimensional arrays; The two dimensions of a matrix are known as its rows and columns; When doing computations, linear transformations are treated as matrices; A matrix is a rectangular arrangement of scalars, and two matrices can be added or multiplied; The product of two matrices shows the result of doing one transformation followed by another (from right to left), and if the transformations are done in reverse order the result is usually different; Matrices have wide applications in engineering, physics, economics, and statistics as well as in various branches of mathematics; The inverse of a matrix, if exists, is unique; All elementary matrices are nonsingular, meaning that they all have their inverse pairs; An elementary matrix can be obtained by performing any one of the three operations on an identity matrix.**     