Matrices

Sunday, 27 May 2018

10:07 PM

An matrix is an array of rows and columns of numbers

Matrices can be added provided that they are the same size

A zero matrix has every entry as zero (0)

Matrix Multiplication

When dealing with multi-row multiplication, do them column by column

The product is only defined when the number of columns of A is equal to the number of rows in B

Multiplication / functions of matrices can only be performed side by side
i.e. you cannot do =>

Machine generated alternative text:
arnple 7. For
—2
—1
-2
1
1
2
and
product AX (bij) can be easily obtained.
—14
A
2
Hence
14
1
AX
1
A
2
2
3
—1
—2
—3
A
14
2
3
1
3
—14
11
11

Identity matrix

The first diagonal of a square matrix is 1

Denoted by or I if there is no risk of ambiguity

If and are solutions of then so are and for any scalar .