Introduction To Matrices

Introduction

Not sure how much I will do about Matrices as I used to understand.

General

Unlike computing Matrices start at one on both axis. Rows are always referred to first. So 2,4 refers to row 2, element 4. In this case 12 \begin{bmatrix} 1 & 4 & -4 & 0 \\ 1 & 4 & 2 & 12 \\ 2 & -3 & -1 & 3 \end{bmatrix} So the order of the matrix is the row but column so this is 3x4 matrix. Where rows = columns it is referred to as square matrix.

Adding Matrices

To add Matrices they must be the same order (size) Given.

$A=\left[\begin{array}{cc}2& 3\\ 5& -4\end{array}\right]$

$B=\left[\begin{array}{cc}7& 4\\ -3& 5\end{array}\right]$

$A+B=\left[\begin{array}{cc}9& 7\\ 2& 1\end{array}\right]$

Subtracting Matrices

To subtract Matrices they must be the same order (size) Given.

$A=\left[\begin{array}{cc}2& 3\\ 5& -4\end{array}\right]$

$B=\left[\begin{array}{cc}7& 4\\ -3& 5\end{array}\right]$

$A-B=\left[\begin{array}{cc}-5& -1\\ 8& -9\end{array}\right]$

Multiplying by a number

So 4 x